Powdered materials including carbonaceous structures for lithium-sulfur battery cathodes

ABSTRACT

A composition of matter suitable for incorporation into a battery electrode is disclosed. In some implementations, the composition of matter may include pores that may be defined in size or shape by several carbonaceous particles. Each of the particles may have multiple regions such that adjacent regions are separated from each other by some of the pores. Deformable regions may be distributed throughout a perimeter of each of the particles, for example, to accommodate coalescence of multiple adjacent particles. The composition of matter may also include a plurality of aggregates and a plurality of agglomerates, where each aggregate includes a multitude of the particles joined together, and each agglomerate includes a multitude of the aggregates joined together.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Patent Application is a continuation-in-part application and claimspriority to U.S. patent application Ser. No. 17/236,291 entitled“TERNARY SOLVENT PACKAGE FOR LITHIUM-SULFUR BATTERIES” filed on Apr. 21,2021, which claims priority to U.S. Provisional Patent Application No.63/019,145, entitled “RUBBER VULCANIZATION ACCELERATORS AS ELECTROLYTEADDITIVES” filed on May 1, 2020, and to U.S. Provisional PatentApplication No. 63/018,930, entitled “PREVENTING POLYSULFIDE MIGRATION”filed on May 1, 2020, and is a continuation-in-part application andclaims priority to U.S. patent application Ser. No. 17/209,038 entitled“CARBON COMPOSITE ANODE WITH EX-SITU ELECTRODEPOSITED LITHIUM” filed onMar. 22, 2021, which is a continuation-in-part application of and claimspriority to U.S. patent application Ser. No. 16/942,229 entitled“CARBON-BASED STRUCTURES FOR INCORPORATION INTO LITHIUM (LI) ION BATTERYELECTRODES filed on Jul. 29, 2020, which is a continuation-in-partapplication of and claims priority to U.S. patent application Ser. No.16/785,020 entitled “3D SELF-ASSEMBLED MULTI-MODAL CARBON BASEDPARTICLE” filed on Feb. 7, 2020 and to U.S. patent application Ser. No.16/785,076 entitled “3D SELF-ASSEMBLED MULTI-MODAL CARBON BASEDPARTICLES INTEGRATED INTO A CONTINUOUS FILM LAYER” filed on Feb. 7,2020, both of which claim priority to U.S. Provisional PatentApplication No. 62/942,103 entitled “3D HIERARCHICAL MESOPOROUSCARBON-BASED PARTICLES INTEGRATED INTO A CONTINUOUS ELECTRODE FILMLAYER” filed on Nov. 30, 2019 and to U.S. Provisional Patent ApplicationNo. 62/926,225 entitled “3D HIERARCHICAL MESOPOROUS CARBON-BASEDPARTICLES INTEGRATED INTO A CONTINUOUS ELECTRODE FILM LAYER” filed onOct. 25, 2019, all of which are assigned to the assignee hereof. ThisPatent Application also claims the benefit of priority to U.S.Provisional Patent Application No. 63/179,106, entitled “LI-S BATTERYLI-PROTECTIVE LAYER FOR LONG TERM STABLE ANODES” filed on Apr. 23, 2021,which is assigned to the assignee hereof. The disclosures of all priorApplications are considered part of and are incorporated by reference inthis Patent Application in their respective entireties.

TECHNICAL FIELD

This disclosure relates generally to batteries, and, more particularly,to lithium-ion batteries that can compensate for operational cyclelosses.

DESCRIPTION OF RELATED ART

Recent developments in batteries allow consumers to use electronicdevices in many new applications. However, further improvements inbattery technology are desirable.

SUMMARY

This Summary is provided to introduce in a simplified form a selectionof concepts that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tolimit the scope of the claimed subject matter.

One innovative aspect of the subject matter described in this disclosurecan be implemented as a composition of matter suitable for incorporationinto a battery electrode. In one implementation, the composition ofmatter may include pores that may be defined in size or shape by severalcarbonaceous particles. Each of the particles may have multiple regionsnested within each other such that adjacent regions are separated fromeach other by some of the pores. Deformable regions may be distributedthroughout a perimeter of each of the particles, for example, toaccommodate coalescence of multiple adjacent particles. In some aspects,the deformable regions may define the perimeters of one or morerespective particles. The composition of matter may also include aplurality of aggregates and a plurality of agglomerates, where eachaggregate includes a multitude of the particles joined together, andeach agglomerate includes a multitude of the aggregates joined together.

In some implementations, each of the particles may have a principaldimension in between 20 nanometers (nm) and 150 nm. Each of theaggregates may have a principal dimension in between 10 nanometers (nm)and 10 micrometers (μm). Each of the agglomerates may have a principaldimension in between 0.1 μm and 1,000 μm. At least some of the pores maybe dispersed throughout one or more of the particles or the aggregates,where each of the pores may have a principal dimension in between 0 nmand 100 nm.

In one implementation, each of the particles may include a firstporosity region and a second porosity region that is positioned adjacentto the first porosity region. The first porosity region may have a firsttype of pores and the second porosity region may have a second type ofpores, such that the first porosity region has a different porosity thanthe second porosity region. As such, the first type of pores may have afirst pore density, and the second type of pores have a second poredensity. For example, the first porosity region may have a first poredensity between 0.0 cubic centimeters (cc)/g and 2.0 cc/g, and thesecond porosity region may have a second pore density between 1.5 and5.0 cc/g. In some aspects, the second porosity region may be at leastpartially encapsulated by the first porosity region.

In some implementations, some of the pores may be interspersedthroughout the agglomerates, where at least some of the pores have aprincipal dimension in between 1.3 nm and 32.3 nm. Electricallyconductive additives may be dispersed within at least some of the pores.In some aspects, the composition of matter may have exposed carbonsurfaces with a surface area in between 10 m²/g to 3,000 m²/g and/or acomposite surface area (e.g., with sulfur micro-confined within thepores) in between 10 m²/g to 3,000 m²/g. In one implementation, thecomposition of matter may have an electrical conductivity in between 100S/m to 20,000 S/m at a pressure of 12,000 pounds per square in (psi).

In one implementation, the particles, aggregates, and/or agglomeratesmay include exposed carbon surfaces that may assist in the nucleation ofsulfur, such that the composition of matter has a sulfur to carbonweight ratio between approximately 1:5 to 10:1. In some aspects, some ofthe agglomerates are connected to each other with one or morepolymer-based binders.

Details of one or more implementations of the subject matter describedin this disclosure are set forth in the accompanying drawings and thedescription below. Other features, aspects, and advantages will becomeapparent from the description, the drawings, and the claims. Note thatthe relative dimensions of the following figures may not be drawn toscale.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a diagram depicting an example electrochemical cell,according to some implementations.

FIG. 2 shows a diagram depicting another example electrochemical cell,according to some implementations.

FIG. 3 shows a diagram of an example of an electrode of anelectrochemical cell, according to some implementations.

FIG. 4 shows a diagram a diagram of a portion of an example battery thatincludes a protective lattice, according to some implementations.

FIG. 5 shows a diagram of an anode structure including a tin fluoride(SnF₂) layer, according to some implementations.

FIG. 6 shows a diagram of an enlarged portion of the anode structure ofFIG. 5, according to some implementations.

FIG. 7 shows a diagram of a polymeric network of a battery, according tosome implementations.

FIG. 8A shows a diagram of an example carbonaceous particle with gradedporosity, according to some implementations.

FIG. 8B shows a diagram of an example of a tri-zone particle, accordingto some implementations.

FIG. 8C shows an example step function representative of average porevolumes in each of the regions of the tri-zone particle of FIG. 8B,according to some implementations.

FIG. 8D shows a graph depicting an example distribution of pore volumeversus pore width of an example carbonaceous particle, according to someimplementations.

FIGS. 9A and 9B show electron micrographs of example carbonaceousparticles, aggregates, and/or agglomerates depicted in FIG. 8A and/orFIG. 8B, according to some implementations.

FIGS. 10A and 10B show transmission electron microscope (TEM) images ofcarbonaceous particles treated with carbon dioxide (CO₂), according tosome implementations.

FIG. 11 shows a diagram depicting carbon porosity types prevalent in theanodes and/or the cathodes of the present disclosure, according to someimplementations.

FIG. 12 shows a graph depicting cumulative pore volume versus pore widthfor micropores and mesopores dispersed throughout the anode or cathodeof a battery, according to some implementations.

FIG. 13 shows graphs depicting battery performance per cycle number,according to some implementations.

FIG. 14 shows a bar chart depicting capacity per cycle number, accordingto some implementations.

FIG. 15 shows graphs depicting battery performance per cycle number,according to some implementations.

FIG. 16 shows a graph depicting battery discharge capacity per cyclenumber, according to some implementations.

FIG. 17 shows a graph depicting battery discharge capacity per cyclenumber, according to some implementations.

FIG. 18 shows a graph depicting battery specific discharge capacity forvarious TB T-containing electrolyte mixtures, according to someimplementations.

FIG. 19 shows graphs depicting battery specific discharge capacity percycle number for the battery of FIG. 1, according to someimplementations.

FIG. 20 shows graphs depicting battery specific discharge capacity anddischarge capacity retention per cycle number for the battery of FIG. 2,according to other implementations.

FIG. 21 shows graphs depicting battery specific discharge capacity anddischarge capacity retention per cycle number for the battery of FIG. 2,according to some other implementations.

Like reference numbers and designations in the various drawings indicatelike elements.

DETAILED DESCRIPTION

The following description is directed to some example implementationsfor the purposes of describing innovative aspects of this disclosure.However, a person having ordinary skill in the art will readilyrecognize that the teachings herein can be applied in a multitude ofdifferent ways. The described implementations can be implemented in anytype of electrochemical cell, battery, or battery pack, and can be usedto compensate for various performance related deficiencies. As such, thedisclosed implementations are not to be limited by the examples providedherein, but rather encompass all implementations contemplated by theattached claims. Additionally, well-known elements of the disclosurewill not be described in detail or will be omitted so as not to obscurethe relevant details of the disclosure.

Batteries typically include several electrochemical cells that can beconnected to each other to provide electric power to a wide variety ofdevices such as (but not limited to) mobile phones, laptops, electricvehicles (EVs), factories, and buildings. Certain types of batteries,such as lithium-ion or lithium-sulfur batteries, may be limited inperformance by the type of electrolyte used or by uncontrolled batteryside reactions. As a result, optimization of the electrolyte may improvethe cyclability, the specific discharge capacity, the discharge capacityretention, the safety, and the lifespan of a respective battery. Forexample, in an unused or “fresh” battery, lithium ions are transportedfreely from the anode to the cathode upon activation and later duringinitial and subsequent discharge cycles. Then, during battery chargecycles, lithium ions may be forced to migrate back from theirelectrochemically favored positions in the cathode to the anode, wherethey are stored for subsequent use. This cyclical discharge-chargeprocess associated with rechargeable batteries can result in thegeneration of undesirable chemical species that can interfere with thetransport of lithium ions to and from the cathode during respectivedischarge and charge of the battery. Specifically, lithium-containingpolysulfide intermediate species (referred to herein as “polysulfides”)are generated when lithium ions interact with elemental sulfur (or, insome configurations, lithium sulfide, Li₂S) present in the cathode.These polysulfides are soluble in the electrolyte and, as a result,diffuse throughout the battery during operational cycling, therebyresulting in loss of active material from cathode. Generation ofexcessive concentration levels of polysulfides can result in unwantedbattery capacity decay and cell failure during operational cycling,potentially reducing the driving range for electric vehicles (EVs) andincreasing the frequency with which such EVs need recharging.

In some cases, polysulfides participate in the formation of inorganiclayers in a solid electrolyte interphase (SEI) provided in the battery.In one example, the anode may be protected by a stable inorganic layerformed in the electrolyte and containing 0.020 M Li₂S₅ (0.10 M sulfur)and 5.0 wt % LiNO₃. The anode with a lithium fluoride and polysulfides(LiF—Li₂S_(x)) may enrich the SEI and result in a stable Coulombicefficiency of 95% after 233 cycles for Li—Cu half cells, whilepreventing formation of lithium dendrites or other uncontrolled lithiumgrowths that can extend from the anode to the cathode and result in afailed or ruptured cell. However, when polysulfides are generated atcertain concentrations (such as greater than 0.50 M sulfur), formationof the SEI may be hindered. As a result, lithium metal from the anodemay be undesirably etched, creating a rough and imperfect surfaceexposed to the electrolyte. This unwanted deterioration (etching) of theanode due to a relatively high concentration of polysulfides mayindicate that polysulfide dissolution and diffusion may be limitingbattery performance.

In some implementations, the porosity of a carbonaceous cathode may beadjusted to achieve a desired balance between maximizing energy densityand inhibiting the migration of polysulfides into and/or throughout thebattery's electrolyte. As used herein, carbonaceous may refer tomaterials containing or formed of one or more types or configuration ofcarbon. For example, cathode porosity may be higher in sulfur and carboncomposite cathodes than in conventional lithium-ion battery electrodes.Denser electrodes with relatively low porosity may minimize electrolyteintake, parasitic weight, and cost. Sulfur utilization may be limited bythe solubility of polysulfides and conversion from those polysulfidesinto lithium sulfide (Li₂S). The conversion of polysulfides into lithiumsulfide may be based on the accessible surface area of the cathode.Aspects of the present disclosure recognize that cathode porosity may beadjusted based on electrolyte constituent materials to maximize batteryvolumetric energy density. In addition, or in the alternative, one ormore protective layers or regions can be added to surfaces of thecathode and/or the anode exposed to the electrolyte to adjust cathodeporosity levels. In some aspects, these protective layers or regions caninhibit the undesirable migration of polysulfides throughout thebattery.

Various aspects of the subject matter disclosed herein relate to alithium-sulfur battery including a liquid-phase electrolyte, which mayinclude a ternary solvent package and one or more additives. In someimplementations, the lithium-sulfur battery may include a cathode, ananode positioned opposite to the cathode, and an electrolyte. Thecathode may include several regions, where each region may be defined bytwo or more carbonaceous structures adjacent to and in contact with eachother. In some instances, the electrolyte may be interspersed throughoutthe cathode and in contact with the anode. In some aspects, theelectrolyte may include a ternary solvent package and4,4′-thiobisbenzenethiol (TBT). In other instances, the electrolyte mayinclude the ternary solvent package and 2-mercaptobenzothiazole (MBT).

In various implementations, the ternary solvent package may include1,2-Dimethoxyethane (DME), 1,3-Dioxolane (DOL), tetraethylene glycoldimethyl ether (TEGDME) and one or more additives, which may include alithium nitrate (LiNO₃), all which may be in a liquid-phase. In someimplementations, the ternary solvent package may be prepared by mixingapproximately 5,800 microliters (μL) of DME, 2,900 microliters (μL) ofDOL, and 1,300 microliters (μL) of TEGDME with one another to create amixture. Approximately 0.01 mol of lithiumbis(trifluoromethanesulfonyl)imide (LiTFSI) may be dissolved into theternary solvent package to produce an approximate dilution level of 1 MLiTFSI in DME:DOL:TEGDME at a volume ratio of 2:1:1 includingapproximately 2 weight percent (wt. %) lithium nitrate. In otherimplementations, the ternary solvent package may be prepared with 2,000microliters (μL) of DME, 8,000 microliters (μL) of DOL, and 2,000microliters (μL) of TEGDME and include approximately 0.01 mol ofdissolved lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). In someaspects, the ternary solvent package may be prepared at a firstapproximate dilution level of 1 molar (M) LiTFSI in a mixture ofDME:DOL:TEGDME. In other instances, the ternary solvent package may beprepared at a second approximate dilution level of approximately 1 MLiTFSI in DME:DOL:TEGDME at an approximate volume ratio of 1:4:1 andinclude either an addition of 5M TBT solution or an addition of 5M MBTsolution, or an addition of other additives and/or chemical substances.

In various implementations, each carbonaceous structure may include arelatively high-density outer shell region and a relatively low-densitycore region. In some aspects, the core region may be formed within aninterior portion of the outer shell region. The outer shell region mayhave a carbon density between approximately 1.0 grams per cubiccentimeter (g/cc) and 3.5 g/cc. The core region may have a carbondensity of between approximately 0.0 g/cc and 1.0 g/cc or some otherrange lower than the first carbon density. In other implementations,each carbonaceous structure may include an outer shell region and coreregion having the same or similar densities, for example, such that thecarbonaceous structure does not include a graded porosity.

Various regions of the cathode may include microporous channels,mesoporous channels, and macroporous channels interconnected to eachother to form a porous network extending from the outer shell region tothe core region. For example, in some aspects, the porous network mayinclude pores that each have a principal dimension of approximately 1.5nm.

In some implementations, one or more portions of the porous network maytemporarily micro-confine electroactive materials such as (but notlimited to) elemental sulfur within the cathode, which may increasebattery specific capacity by complexing with lithium ions. In someaspects, the ternary solvent package may have a tunable polarity, atunable solubility, and be capable of transporting lithium ions. Inaddition, the ternary solvent package may at least temporarily suspendpolysulfides (PS) during charge-discharge cycles of the battery.

Particular implementations of the subject matter described in thisdisclosure can be implemented to realize one or more potentialadvantages. In some implementations, the porous network formed by theinterconnection of microporous, mesoporous, and macroporous channelswithin the cathode may include a plurality of pores having a multitudeof different pore sizes. In some implementations, the plurality of poresmay include micropores having a pore size less than approximately 2 nm,may include mesopores having a pore size between approximately 5 and 50nm, and may include macropores having a pore size greater thanapproximately 50 nm. The micropores, mesopores, and macropores maycollectively mitigate the undesirable migration or diffusion ofpolysulfides throughout the electrolyte. Since the polysulfide shuttleeffect may result in the loss of active material from the cathode, theability to mitigate or reduce the polysulfide shuttle effect canincrease battery performance.

In one implementation, the micropores may have a pore size ofapproximately 1.5 nm selected to micro-confine elemental sulfur (S₈, orsmaller chains/fragments of sulfur, for example in the form of S₂, S₄ orS₆) pre-loaded into the cathode. The micro-confinement of elementalsulfur within the cathode may allow TBT or MBT complexes generatedduring battery cycling to inhibit the migration of long-chain polysulfides within the mesopores of the cathode. Accumulation of theselong-chain polysulfides within the mesopores of the cathode may causethe cathode to volumetrically expand to retain the polysulfides andthereby reduce the polysulfide shuttle effect. Accordingly, lithium ionsmay continue to transport freely between the anode and the cathode viathe electrolyte without being blocked or impeded by the polysulfides.The free movement of lithium ions throughout the electrolyte withoutinterference by polysulfides can increase battery performance.

In addition, or the alternative, one or more protective layers, sheaths,films, and/or regions (collectively referred to herein as “protectivelayers”) may be disposed on the anode and/or the cathode and/or theseparator and in contact with the electrolyte. The protective layers mayinclude materials capable of binding with polysulfides to impedepolysulfide migration and prevent lithium dendrite formation. In someaspects, the protective layers may be arranged in differentconfigurations and used with any of the electrolyte chemistries and/orcompositions disclosed herein, which in turn may result in completetunability of the battery.

In one implementation, carbonaceous materials may be grafted withfluorinated polymer chains and deposited on one or more exposed surfacesof the anode. The fluorinated polymer chains can be cross-linked into apolymeric network on contact with Lithium metal from the anode surfacevia the Wurtz reaction. The cross-linked polymeric network formationmay, in turn, suppress Lithium metal dendrite formation associated withthe anode, and may also generate Lithium fluoride. Fluorinated polymerswithin the polymeric network may participate in chemical reactionsduring battery operational cycling to yield Lithium fluoride. Formationof the lithium fluoride may involve the chemical binding of lithium ionsfrom the electrolyte with fluorine ions.

In addition, or the alternative, the polymeric network may be combinedwith any of the electrolyte chemistries and/or compositions disclosedherein and/or a protective sheath disposed on the cathode. In oneimplementation, the protective sheath can be formed by combiningcompounds containing di-functional, or higher functionality Epoxy andAmine or Amide compounds. Their intermolecular cross-linking wouldresult in formation of 3D network with high chemical resistance todissolution in electrolyte. Composition, for example, may include atri-functional epoxy compound and a di-amine oligomer-based compound,which may react with each other to produce a protective lattice that canbind to polysulfides generated in the cathode and prevent theirmigration or diffusion into the electrolyte. In addition, the protectivelattice may diffuse through one or more cracks that may form in thecathode due to battery cycling. The protective lattice, when diffusedthroughout such cracks formed in the cathode, may increase thestructural integrity of the cathode and reduce potential rupture of thecathode associated with volumetric expansion.

In various implementations, one or more of the disclosed batterycomponents may be combined with a conformal coating disposed on edges orsurfaces of the anode exposed to the electrolyte. In someimplementations, the conformal coating may include a graded interfacelayer that may replace the polymeric network. In some aspects, thegraded interface layer may include a tin fluoride layer and atin-lithium alloy region formed between the tin fluoride layer and theanode. The tin-lithium alloy region may form a layer of lithium fluorideuniformly dispersed between the anode and the tin-fluoride layer inresponse to operational cycling of the battery.

In various implementations, a lithium-sulfur battery employing variousaspects of the present disclosure may include an electroactive materialextracted from an external source, e.g., a subterranean source and/or anextraterrestrial subterranean source. In such implementations, thecathode may be prepared as a sulfur-free cathode including functionalpores that may microconfine the electroactive material within thecathode. In some aspects, the cathode may include aggregates including amultitude of carbonaceous particles joined together, and may includeagglomerates including a multitude of the aggregates joined together. Inone implementation, the carbonaceous materials used to form the cathode(and/or the anode) may be tuned to define unique pore sizes, sizeranges, and volumes. In some implementations, the carbonaceous particlesmay include non-tri-zone particles with and without tri-zone particles.In other implementations, the carbonaceous particles may not includetri-zone particles. Each tri-zone particle may include micropores,mesopores, and macropores, and both the non-tri-zone and tri-zoneparticles may each have a principal dimension in an approximate range of20 nm to 300 nm. Each of the carbonaceous particles may includecarbonaceous fragments nested within each other and separated fromimmediate adjacent carbonaceous fragments by mesopores. In some aspects,each of the carbonaceous particles may have a deformable perimeter thatchanges in shape and coalesces with adjacent materials.

Some of the pores may be distributed throughout the plurality ofcarbonaceous fragments and/or the deformable perimeters of thecarbonaceous particles. In various implementations, mesopores may beinterspersed throughout the aggregates, and macropores may beinterspersed throughout the plurality of agglomerates. In oneimplementation, each mesopore may have a principal dimension between 3.3nanometers (nm) and 19.3 nm, each aggregate may have a principaldimension in an approximate range between 10 nm and 10 micrometers (μm),and each agglomerate may have a principal dimension in an approximaterange between 0.1 μm and 1,000 μm. As further described below, specificcombinations of pore sizes matched with unique electrolyte formulationsand protective layers can be used to reduce or mitigate the harmfuleffects of unwanted polysulfide diffusion, which may further increasebattery performance.

FIG. 1 shows an example battery 100, according to some implementations.The battery 100 may be a lithium-sulfur electrochemical cell, alithium-ion battery, or a lithium-sulfur battery. The battery 100 mayhave a body 105 that includes a first substrate 101, a second substrate102, a cathode 110, an anode 120 positioned opposite to the cathode 110,and an electrolyte 130. In some aspects, the first substrate 101 mayfunction as a current collector for the anode 120, and the secondsubstrate 102 may function as a current collector for the cathode 110.The cathode 110 may include a first thin film 111 deposited onto thesecond substrate 102, and may include a second thin film 112 depositedonto the first thin film 111. In some implementations, the electrolyte130 may be a liquid-phase electrolyte including one or more additivessuch as lithium nitrate, tin fluoride, lithium iodide, lithiumbis(oxalate)borate (LiBOB), cesium nitrate, cesium fluoride, ionicliquids, lithium fluoride, fluorinated ether, TBT, MBT, DPT and/or thelike. Suitable solvent packages for these example additives may includevarious dilution ratios, including 1:1:1 of 1,3-dioxolane (DOL),1,2-dimethoxyethane, (DME), tetraethylene glycol dimethyl ether(TEGDME), and/or the like.

Although not shown for simplicity, in one implementation, a lithiumlayer may be electrodeposited on one or more exposed carbon surfaces ofthe anode 120. In some instances, the lithium layer may includeelemental lithium provided by the ex-situ electrodeposition of lithiumonto exposed surfaces of the anode 120. In some aspects, the lithiumlayer may include lithium, calcium, potassium, magnesium, sodium, and/orcesium, where each metal may be ex-situ deposited onto exposed carbonsurfaces of the anode 120. The lithium layer may provide lithium ionsavailable for transport to-and-from the cathode 110 during operationalcycling of the battery 100. As a result, the battery 100 may not need anadditional lithium source for operation. Instead of using lithiumsulfide, elemental sulfur (S₈) may be pre-loaded in various pores orporous networks formed in the cathode 110. During operational cycling ofthe battery, the elemental sulfur may form lithium-sulfur complexes thatcan microconfine (at least temporarily) greater amounts of lithium thanconventional cathode designs. As a result, the battery 100 mayoutperform batteries that rely on such conventional cathode designs.

In various implementations, the lithium layer may dissociate and/orseparate into lithium ions 125 and electrons 174 during a dischargecycle of the battery 100. The lithium ions 125 may migrate from theanode 120 towards the cathode 110 through the electrolyte 130 to theirelectrochemically favored positions within the cathode 110, as depictedin the example of FIG. 1. As the lithium ions 125 move through theelectrolyte 130, electrons 174 are released from lithium ions 125 andbecome available to carry charge, and therefore conduct an electriccurrent, between the anode 120 and cathode 110. As a result, theelectrons 174 may travel from the anode 120 to the cathode 110 throughan external circuit to power a load 172. The load 172 may be anysuitable circuit, device, or system such as (but not limited to) alightbulb, consumer electronics, or an electric vehicle (EV).

In some implementations, the battery 100 may include a solid-electrolyteinterphase layer 140. The solid-electrolyte interphase layer 140 may, insome instances, be formed artificially on the anode 120 duringoperational cycling of the battery 100. In such instances, thesolid-electrolyte interphase layer 140 may also be referred to as anartificial solid-electrolyte interphase, or A-SEI. The solid-electrolyteinterphase layer 140, when formed as an A-SEI, may include tin,manganese, molybdenum, and/or fluorine compounds. Specifically, themolybdenum may provide cations, and the fluorine compounds may provideanions. The cations and anions may interact with each other to producesalts such as tin fluoride, manganese fluoride, silicon nitride, lithiumnitride, lithium nitrate, lithium phosphate, manganese oxide, lithiumlanthanum zirconium oxide (LLZO, Li₇La₃Zr₂O₁₂), etc. In some instances,the A-SEI may be formed in response to exposure of lithium ions 125 tothe electrolyte 130, which may include solvent-based solutions includingtin and/or fluorine.

In various implementations, the solid-electrolyte interphase layer 140may be artificially provided on the anode 120 prior to activation of thebattery 100. Alternatively, in one implementation, the solid-electrolyteinterphase layer 140 may form naturally, e.g., during operationalcycling of the battery 100, on the anode 120. In some instances, thesolid-electrolyte interphase layer 140 may include an outer layer ofshielding material that can be applied to the anode 120 as amicro-coating. In this way, formation of the solid-electrolyteinterphase layer 140 on portions of the anode 120 facing the electrolyte130 may result from electrochemical reduction of the electrolyte 130,which in turn may reduce uncontrolled decomposition of the anode 120.

In some implementations, the battery 100 may include a barrier layer 142that flanks the solid-electrolyte interphase layer 140, for example, asshown in FIG. 1. The barrier layer 142 may include a mechanical strengthenhancer 144 coated and/or deposited on the anode 120. In some aspects,the mechanical strength enhancer 144 may provide structural support forthe battery 100, may prevent lithium dendrite formation from the anode120, and/or may prevent protrusion of lithium dendrite throughout thebattery 100. In some implementations, the mechanical strength enhancer144 may be formed as a protective coating over the anode 120, and mayinclude one or more carbon allotropes, carbon nano-onions (CNOs),nanotubes (CNTs), reduced graphene oxide, graphene oxide (GO), and/orcarbon nano-diamonds. In some instances, the solid-electrolyteinterphase layer 140 may be formed within the mechanical strengthenhancer 144.

In some implementations, the first substrate 101 and/or the secondsubstrate 102 may be a solid copper metal foil and may influence theenergy capacity, rate capability, lifespan, and long-term stability ofthe battery 100. For example, to control energy capacity and otherperformance attributes of the battery 100, the first substrate 101and/or the second substrate 102 may be subject to etching, carboncoating, or other suitable treatment to increase electrochemicalstability and/or electrical conductivity of the battery 100. In otherimplementations, the first substrate 101 and/or the second substrate 102may include or may be formed from a selection of aluminum, copper,nickel, titanium, stainless steel and/or carbonaceous materialsdepending on end-use applications and/or performance requirements of thebattery 100. For example, the first substrate 101 and/or the secondsubstrate 102 may be individually tuned or tailored such that thebattery 100 meets one or more performance requirements or metrics.

In some aspects, the first substrate 101 and/or the second substrate 102may be at least partially foam-based or foam-derived, and can beselected from any one or more of metal foam, metal web, metal screen,perforated metal, or sheet-based three-dimensional (3D) structures. Inother aspects, the first substrate 101 and/or the second substrate 102may be a metal fiber mat, metal nanowire mat, conductive polymernanofiber mat, conductive polymer foam, conductive polymer-coated fiberfoam, carbon foam, graphite foam, or carbon aerogel. In some otheraspects, the first substrate 101 and/or second substrate 102 may becarbon xerogel, graphene foam, graphene oxide foam, reduced grapheneoxide foam, carbon fiber foam, graphite fiber foam, exfoliated graphitefoam, or any combination thereof.

FIG. 2 shows another example battery 200, according to someimplementations. The battery 200 may be similar to the battery 100 ofFIG. 1 in many respects, such that description of like elements is notrepeated herein. In some implementations, the battery 200 may be anext-generation battery, such as a lithium-metal battery and/or asolid-state battery featuring a solid-state electrolyte. In otherimplementations, the battery 200 may include a liquid-phase electrolyte230 and may therefore include any of the protective layers and/orelectrolyte chemistries or compositions disclosed herein.

In some other implementations, the electrolyte 230 may be solid orsubstantially solid. For example, in some instances, the electrolyte 230may begin in a gel phase and then later solidify upon activation of thebattery 200. The battery 200 may reduce specific capacity or energylosses associated with the polysulfide shuttle effect by replacingconventional carbon scaffolded anodes with a single solid metal layer oflithium deposited in an initially empty cavity. For example, while theanode 120 of the battery 100 of FIG. 1 may include carbon scaffolds, theanode 220 of the battery 200 of FIG. 2 may be a lithium-metal anodedevoid of any carbon material. In one implementation, the lithium-metalanode may be formed as a single solid lithium metal layer and referredto as a “lithium metal anode.”

Energy density gains associated with various cathode materials may bebased on whether lithium metal is pre-loaded into the cathode 210 and/oris prevalent in the electrolyte 230. Either the cathode 210 and/or theelectrolyte 230 may provide lithium available for lithiation of theanode 220. For example, batteries having high-capacity cathodes may needthicker or energetically denser anodes in order to supply the increasedquantities of lithium needed for usage by the high-capacity cathodes. Insome implementations, the anode 220 may include scaffolded carbonaceousstructures capable of being incrementally filled with lithium depositedtherein. These carbonaceous structures may be capable of retaininggreater amounts of lithium within the anode 220 as compared toconventional graphitic anodes, which may be limited to solely hostinglithium intercalated between alternating graphene layers or may beelectroplated with lithium. For example, conventional graphitic anodesmay use six carbon atoms to hold a single lithium atom. In contrast, byusing a pure lithium metal anode, such as the anode 220, batteriesdisclosed herein may reduce or even eliminate carbon use in the anode220, which may allow the anode 220 to store greater amounts of lithiumin a relatively smaller volume than conventional graphitic anodes. Inthis way, the energy density of the battery 200 may be greater thanconventional batteries of a similar size.

Lithium metal anodes, such as the anode 220, may be prepared to functionwith a solid-state electrolyte designed to inhibit the formation andgrowth of lithium dendrites from the anode. In some aspects, asolid-state separator 250 may further limit dendrite formation andgrowth. The separator 250 may have a similar ionic conductivity as theliquid-phase electrolyte 130 of FIG. 1 yet still reduce lithium dendriteformation. In some aspects, the separator 250 may be formed from aceramic containing material and may, as a result, fail to chemicallyreact with metallic lithium. As a result, the separator 250 may be usedto control lithium ion transport through pores dispersed across theseparator 250 while concurrently preventing a short-circuit by impedingthe flow or passage of electrons through the electrolyte 230.

In one implementation, a void space (not shown for simplicity) may beformed within the battery 200 at or near the anode 220. Operationalcycling of the battery 200 in this implementation may result in thedeposition of lithium into the void space. As a result, the void spacemay become or transform into a lithium-containing region (such as asolid lithium metal layer) and function as the anode 220. In someaspects, the void space may be created in response to chemical reactionsbetween a metal-containing electrically inactive component and agraphene-containing component of the battery 200. Specifically, thegraphene-containing component may chemically react with lithiumdeposited into the void space during operational cycling and producelithiated graphite (LiC₆) or a patterned lithium metal. The lithiatedgraphite produced by the chemical reactions may generate or lead to thegeneration and/or liberation of lithium ions and/or electrons that canbe used to carry electric charge or a “current” between the anode 220and the cathode 210 during discharge cycles of the battery 200.

And, in implementations for which the anode 220 is a solid lithium metallayer, the battery 200 may be able to hold more electroactive materialand/or lithium per unit volume (as compared to batteries with scaffoldedcarbon and/or intercalated lithiated graphite anodes). In some aspects,the anode 220, when prepared as a solid lithium metal layer, may resultin the battery 200 having a higher energy density and/or specificcapacity than batteries with scaffolded carbon and/or intercalatedlithiated graphite anodes, thereby resulting in longer discharge cycletimes and additional power output per unit time. In instances for whichuse of a solid-state electrolyte is not desired or not optimal, theelectrolyte 230 of the battery 200 of FIG. 2 may be prepared with any ofthe liquid-phase electrolyte chemistries and/or compositions disclosedherein. In addition, or in the alternative, the electrolyte 230 mayinclude lithium and/or lithium ions available for cyclical transportfrom the anode 220 to the cathode 210 and vice-versa during dischargeand charge cycles, respectively.

To reduce the migration of polysulfides 282 generated from elementalsulfur 281 pre-loaded in the cathode 210 into the electrolyte 230, thebattery 200 may include one or more unique polysulfide retentionfeatures. For example, given that polysulfides are soluble in theelectrolyte 230, some polysulfides may be expected to drift or migratefrom the cathode 210 towards the anode 220 due to differences inelectrochemical potential, chemical gradients, and/or other phenomena.The migration of polysulfides 282, especially long-chain formpolysulfides, may impede the transport of lithium ions from the anode220 to the cathode 210, which in turn may reduce the number of electronsavailable to generate an electric current that can power a load 272,such as an electric vehicle (EV). In some aspects, lithium ions may betransported from one or more start positions 226 in or near the anode220 along a transport pathway 225 to one or more end positions 227 in ornear the cathode 210, as depicted in the example of FIG. 2.

In some implementations, a polymeric network 285 may be disposed on theanode 220 to reduce the uncontrolled migration of polysulfides 282 fromthe anode 220 to the cathode 210. The polymeric network 285 may includeone or more layers of carbonaceous materials grafted with fluorinatedpolymer chains cross-linked with each other via the Wurtz reaction uponexposure to Lithium anode surface. The carbonaceous materials in thepolymeric network 285, which may include (but are not limited tographene, few layer graphene, FLG, many layer graphene, and MLG), may bechemically grafted with fluorinated polymer chains containingcarbon-fluorine (C—F) bonds. These C—F bonds may chemically react withlithium metal from the surface of the anode 220 to produce highly ionicCarbon-Lithium bonds (C—Li). These formed C—Li bonds, in turn, may reactwith C—F bonds of polymer chains to form new Carbon-Carbon bonds thatcan also cross-link the polymer chains into (and thereby form) thepolymeric network and generate lithium fluoride (LiF).

The resulting lithium fluoride may be uniformly distributed along theentire perimeter of the polymeric network 285, such that lithium ionsare uniformly consumed to produce an interface layer 283 that may formor otherwise include lithium fluoride during battery cycling. Theinterface layer 283 may extend along a surface or portion of the anode220 facing the cathode 210, as shown in FIG. 2. As a result, the lithiumions 225 are less likely to combine and/or react with each other and aremore likely to combine and/or react with fluorine atoms made availableby the fluorinated polymer chains in the polymeric network 285. Theresulting reduction of lithium-lithium chemical reactions decreaseslithium-lithium bonding responsible for undesirable lithium-metaldendrite formation. In addition, in some implementations, the polymericnetwork 285 may replace the interphase layer 240 that either naturallyor artificially develops between the anode 220 and the electrolyte 230.

In one implementation, the interface layer 283 of the polymeric network285 is in contact with the anode 220, and a protective layer 284 isdisposed on top of the interface layer 283 (such as between theinterface layer 283 and the interface layer 240). In some aspects, theinterface layer 283 and the protective layer 284 may collectively definea gradient of cross-linked fluoropolymer chains of varying degrees ofdensity, for example, as described with reference to FIG. 7.

In some other implementations, the battery 200 may include a protectivelattice 280 disposed on the cathode 210. The protective lattice 280 mayinclude a tri-functional epoxy compound and a di-amine oligomer-basedcompound that may chemically react with each other to produce nitrogenand oxygen atoms. The nitrogen and oxygen atoms made available by theprotective lattice 280 can bind with the polysulfides 282, therebyconfining the polysulfides 282 within the cathode 210 and/or theprotective lattice 280. Either of the cathode 210 and/or the protectivelattice 280 may include carbon-carbon bonds and/or regions capable offlexing and/or volumetrically expanding during operational cycling ofthe battery 200, which may confine polysulfides 282 generated during theoperational cycling to the cathode 210.

The electrolyte 130 of FIG. 1 and the electrolyte 230 of FIG. 2 may beprepared according to one or more recipes disclosed herein. For example,a ternary solvent package used in the electrolyte 130 and/or theelectrolyte 230 may include DME, DOL and TEGDME. In one implementation,a solvent mixture may be prepared by mixing 5800 μL DME, 2900 μL DOL and1300 μL TEGDME and stifling at room temperature (77° F. or 25° C.).Next, 0.01 mol (2,850.75 mg) of LiTFSI may be weighed. Afterwards, the0.01 mol of LiTFSI may be dissolved in solvent mixture by stirring atroom temperature to prepare approximately 10 mL 1 M LiTFSI inDME:DOL:TEGDME (volume:volume:volume 1:4:1). Finally, approximately 223mg LiNO₃ may be added to 10 mL solution to produce 10 mL 1 M LiTFSI inDME:DOL:TEGDME (volume:volume:volume=58:29:13) with approximately 2 wt.% LiNO₃.

In addition, or the alternative, a ternary solvent package used in theelectrolyte 130 and/or the electrolyte 230 may include DME, DOL, TEGDME,and TBT or MBT. A solvent mixture may be prepared by mixing 2,000 μLDME, 8,000 μL DOL and 2,000 μL TEGDME and stirring at room temperature(68° F. or 25° C.). Next, 0.01 mol (2,850.75 mg) of LiTFSI may beweighed and dissolved in approximately 3 mL of the solvent mixture bystirring at room temperature. Next, the dissolved LiTFSI and anadditional solvent mixture (˜8,056 mg) may be mixed in a 10 mLvolumetric flask to produce approximately 1 M LiTFSI in DME:DOL:TEGDME(volume:volume:volume 1:4:1). Finally, approximately 0.05 mmol (˜12.5mg) TBT or MBT may be added to the 10 mL solution to produce 10 mL of 5MTBT or MBT solution.

FIG. 3 shows an example electrode 300, according to someimplementations. In various implementations, the electrode 300 may beone example of the cathode 110 and/or the anode 110 of the battery 100of FIG. 1. In some other implementations, the electrode 300 may be oneexample of the cathode 210 of the battery 200 of FIG. 2. When theelectrode 300 is implemented as a cathode (such as the cathode 110 ofthe battery 100 of FIG. 1), the electrode 300 may temporarilymicroconfine an electroactive material, such as elemental sulfur, whichmay decrease the amount of sulfur available for reacting with lithium toproduce polysulfides. In some aspects, the electrode 300 may provide anexcess supply of lithium and/or lithium ions that can compensate forfirst-cycle operational losses associated with lithium-based batteries.

In some implementations, the electrode 300 may be porous and receptiveof a liquid-phase electrolyte, such as the electrolyte 130 of FIG. 1.Electroactive species, such as lithium ions 125 suspended in theelectrolyte 130, may chemically react with elemental sulfur pre-loadedinto pores of the electrode 300 to produce polysulfides, which in turnmay be trapped in the electrode 300 during battery cycling. In someaspects, the electrode 300 may expand in volume along one or moreflexure points to retain additional quantities of polysulfides createdduring battery cycling. By confining the polysulfides within theelectrode 300, aspects of the subject matter disclosed herein may allowthe lithium ions 125 to flow freely through the electrolyte 130 from theanode 120 to the cathode 110 during discharge cycles of the battery 100(e.g., without being impeded by the polysulfides). For example, whenlithium ions 125 reach the cathode 110 and react with elemental sulfurcontained in or associated with the cathode 110, sulfur is reduced tolithium polysulfides (Li₂S_(x)) at decreasing chain lengths according tothe order Li₂S₈→Li₂S₆→Li₂S₄→Li₂S₂→Li₂S, where 2≤x≤8). Higher orderpolysulfides may be soluble in various types of solvents and/orelectrolytes, thereby interfering with the lithium ion transportnecessary for healthy battery operation. Retention of such higher orderpolysulfides by the electrode 300 thereby allows the lithium ions 125 toflow more freely through the electrolyte 130, which in turn may increasethe number of electrons available to carry charge from the anode 120 tothe cathode 110.

The electrode 300 may include a body region 301 defined by a width 305,and may include a first thin film 310 and a second thin film 320. Thefirst thin film 310 may include a plurality of first aggregates 312 thatjoin together to form a first porous structure 316 of the electrode 300.In some instances, the first porous structure 316 may have an electricalconductivity between approximately 0 and 500 S/m. In other instances,the first electrical conductivity may be between approximately 500 and1,000 S/m. In some other instances, the first electrical conductivitymay be greater than 1,000 S/m. In some aspects, the first aggregates 312may include carbon nano-tubes (CNTs), carbon nano-onions (CNOs), flakygraphene, crinkled graphene, graphene grown on carbonaceous materials,and/or graphene grown on graphene.

In some implementations, the first aggregates 312 may be decorated witha plurality of first nanoparticles 314. In some instances, the firstnanoparticles 314 may include tin, lithium alloy, iron, silver, cobalt,semiconducting materials and/or metals such as silicon and/or the like.In some aspects, CNTs, due to their ability to provide high exposedsurface areas per unit volume and stability at relatively hightemperatures (such as above 77° F. or 25° C.), may be used as a supportmaterial for the first nanoparticles 314. For example, the firstnanoparticles 314 may be immobilized (such as by decoration, deposition,surface modification or the like) onto exposed surfaces of CNTs and/orother carbonaceous materials. The first nanoparticles 314 may react withchemically available carbon on exposed surfaces of the CNTs and/or othercarbonaceous materials.

The second thin film 320 may include a plurality of second aggregates322 that join together to form a second porous structure 326. In someinstances, the electrical conductivities of the first porous structure316 and/or the second porous structure 326 may be between approximately0 S/m and 250 S/m. In instances for which the first porous structure 316includes a higher concentration of aggregates than the second porousstructure 326, the first porous structure 316 may have a higherelectrical conductivity than the second porous structure 326. In oneimplementation, the first electrical conductivity may be betweenapproximately 250 S/m and 500 S/m, while the second electricalconductivity may be between approximately 100 S/m and 250 S/m. Inanother implementation, the second electrical conductivity may bebetween approximately 250 S/m and 500 S/m. In yet anotherimplementation, the second electrical conductivity may be greater than500 S/m. In some aspects, the second aggregates 322 may include CNTs,CNOs, flaky graphene, crinkled graphene, graphene grown on carbonaceousmaterials, and/or graphene grown on graphene.

The second aggregates 322 may be decorated with a plurality of secondnanoparticles 324. In some implementations, the second nanoparticles 324may include iron, silver, cobalt, semiconducting materials and/or metalssuch as silicon and/or the like. In some instances, CNTs may also beused as a support material for the second nanoparticles 324. Forexample, the second nanoparticles 324 may be immobilized (such as bydecoration, deposition, surface modification or the like) onto exposedsurfaces of CNTs and/or other carbonaceous materials. The secondnanoparticles 324 may react with chemically available carbon on exposedsurfaces of the CNTs and/or other carbonaceous materials.

In some aspects, the first thin film 310 and/or the second thin film 320(as well as any additional thin films disposed on their respectiveimmediately preceding thin film) may be created as a layer or region ofmaterial and/or aggregates. The layer or region may range from fractionsof a nanometer to several microns in thickness, such as betweenapproximately 0 and 5 microns, between approximately 5 and 10 microns,between approximately 10 and 15 microns, or greater than 15 microns. Anyof the materials and/or aggregates disclosed herein, such as CNOs, maybe incorporated into the first thin film 310 and/or the second thin film320 to result in the described thickness levels.

In some implementations, the first thin film 310 may be deposited ontothe second substrate 102 of FIG. 1 by chemical deposition, physicaldeposition, or grown layer-by-layer through techniques such as Frank-vander Merwe growth, Stranski-Krastonov growth, Volmer-Weber growth and/orthe like. In other implementations, the first thin film 310 may bedeposited onto the second substrate 102 by epitaxy or other suitablethin-film deposition process involving the epitaxial growth ofmaterials. The second thin film 320 and/or subsequent thin films may bedeposited onto their respective immediately preceding thin film in amanner similar to that described with reference to the first thin film310.

In various implementations, each of the first aggregates 312 and/or thesecond aggregates 322 may be a relatively large particle formed by manyrelatively small particles bonded or fused together. As a result, theexternal surface area of the relatively large particle may besignificantly smaller than combined surface areas of the many relativelysmall particles. The forces holding an aggregate together may be, forexample, covalent, ionic bonds, or other types of chemical bondsresulting from the sintering or complex physical entanglement of formerprimary particles.

As discussed above, the first aggregates 312 may join together to formthe first porous structure 316, and the second aggregates 322 may jointogether to form the second porous structure 326. The electricalconductivity of the first porous structure 316 may be based on theconcentration level of the first aggregates 312 within the first porousstructure 316, and the electrical conductivity of the second porousstructure 326 may be based on the concentration level of the secondaggregates 322 within the second porous structure 326. In some aspects,the concentration level of the first aggregates 312 may cause the firstporous structure 316 to have a relatively high electrical conductivity,and the concentration level of the second aggregates 322 may cause thesecond porous structure 326 to have a relatively low electricalconductivity (such that the first porous structure 316 has a greaterelectrical conductivity than the second porous structure 326). Theresulting differences in electrical conductivities of the first andsecond porous structures 316 and 326 may create an electricalconductivity gradient across the electrode 300. In some implementations,the electrical conductivity gradient may be used to control or adjustelectrical conduction throughout the electrode 300 and/or one or moreoperations of the battery 100 of FIG. 1.

As used herein, the relatively small source particles may be referred toas “primary particles,” and the relatively large aggregates formed bythe primary particles may be referred to as “secondary particles.” Asshown in FIG. 1, FIGS. 8 to 10, and elsewhere throughout the presentdisclosure, the primary particles may be or include multiple graphenesheets, layers, regions, and/or nanoplatelets fused and/or joinedtogether. Thus, in some instances, carbon nano-onions (CNOs), carbonnano-tubes (CNTs), and/or other tunable carbon materials may be used toform the primary particles. In some aspects, some aggregates may have aprincipal dimension (such as a length, a width, and/or a diameter)between approximately 500 nm and 25 μm. Also, some aggregates mayinclude innately-formed smaller collections of primary particles,referred to as “innate particles,” of graphene sheets, layers, regions,and/or nanoplatelets joined together at orthogonal angles. In someinstances, these innate particles may each have a respective dimensionbetween approximately 50 nm and 250 nm.

The surface area and/or porosity of these innate particles may beimparted by secondary processes, such as carbon-activation by a thermal,plasma, or combined thermal-plasma process using one or more of steam,hydrogen gas, carbon dioxide, oxygen, ozone, KOH, ZnCl2, H3PO4, or othersimilar chemical agents alone or in combination. In someimplementations, the first porous structure 316 and/or the second porousstructure 326 may be produced from a carbonaceous gaseous species thatcan be controlled by gas-solid reactions under non-equilibriumconditions. Producing the first porous structure 316 and/or the secondporous structure 326 in this manner may involve recombination ofcarbon-containing radicals formed from the controlled cooling ofcarbon-containing plasma species (which can be generated by excitementor compaction of feedstock carbon-containing gaseous and/or plasmaspecies in a suitable chemical reactor).

In some implementations, the first aggregates 312 and/or the secondaggregates 322 may have a percentage of carbon to other elements, excepthydrogen, within each respective aggregate of greater than 99%. In someinstances, a median size of each aggregate may be between approximately0.1 microns and 50 microns. The first aggregates 312 and/or the secondaggregates 322 may also include metal organic frameworks (MOFs).

In some implementations, the first porous structure 316 and secondporous structure 326 may collectively define a host structure 328, forexample, as shown in FIG. 3. In some instances, the host structure 328may be based on a carbon scaffold and/or may include decorated carbons,for example, as shown in FIG. 8. The host structure 328 may providestructural definition to the electrode 300. In some instances, the hoststructure 328 may be fabricated as a positive electrode and used in thecathode 110 of FIG. 1. In other implementations, the host structure 328may be fabricated as a negative electrode and used in the anode 120 ofFIG. 1. In some other implementations, the host structure 328 mayinclude pores having different sizes, such as micropores, mesopores,and/or macropores defined by the IUPAC. In some instances, at least someof the micropores may have a width of approximately 1.5 nm, which may belarge enough to allow sulfur to be pre-loaded into the electrode 300 andyet small enough to at least temporarily confine polysulfides within theelectrode 300.

The host structure 328, when provided within the electrode 300 as shownin FIG. 3, may include microporous, mesoporous, and/or macroporouspathways created by exposed surfaces and/or contours of the first porousstructure 316 and/or the second porous structure 326. These pathways mayallow the host structure 328 to receive an electrolyte, for example, bytransporting lithium ions towards the cathode 110 of the battery 100.Specifically, the electrolyte 130 may infiltrate the various porouspathways of the host structure 328 and uniformly disperse throughout theelectrode 300 and/or other portions of the battery 100. Infiltration ofthe electrolyte 130 into such regions of the host structure 328 mayallow the lithium ions 125 migrating from the anode 120 towards thecathode 110 to react with elemental sulfur associated with the cathode110 to form lithium-sulfur complexes. As a result, the elemental sulfurmay retain additional quantities of lithium ions that would otherwise beachievable using non-sulfur chemistries such as lithium cobalt oxide(LiCoO) or other lithium-ion cells.

In some aspects, each of the first porous structure 316 and/or thesecond porous structure 326 may have a porosity based on one or more ofa thermal, plasma, or combined thermal-plasma process using one or moreof steam, hydrogen gas, carbon dioxide, oxygen, ozone, KOH, ZnCl2,H3PO4, or other similar chemical agents alone or in combination. Forexample, in one implementation, the macroporous pathways may have aprincipal dimension greater than 50 nm, the mesoporous pathways may havea principal dimension between approximately 20 nm and 50 nm, and themicroporous pathways may have a principal dimension less than 4 nm. Assuch, the macroporous pathways and mesoporous pathways can providetunable conduits for transporting lithium ions 125, and the microporouspathways may confine active materials within the electrode 300.

In some implementations, the electrode 300 may include one or moreadditional thin films (not shown for simplicity). Each of the one ormore additional thin films may include individual aggregatesinterconnected with each other across different thin films, with atleast some of the thin films having different concentration levels ofaggregates. As a result, the concentration levels of any thin film maybe varied (such as by gradation) to achieve particular electricalresistance (or conductance) values. For example, in someimplementations, the concentration levels of aggregates mayprogressively decline between the first thin film 310 and the last thinfilm (such as in a direction 195 depicted in FIG. 1), and/or theindividual thin films may have an average thickness betweenapproximately 10 microns and approximately 200 microns. In addition, orin the alternative, the first thin film 310 may have a relatively highconcentration of carbonaceous aggregates, and the second thin film 320may have a relatively low concentration of carbonaceous aggregates. Insome aspects, the relatively high concentration of aggregatescorresponds to a relatively low electrical resistance, and therelatively low concentration of aggregates corresponds to a relativelyhigh electrical resistance.

The host structure 328 may be prepared with multiple active sites onexposed surfaces of the first aggregates 312 and/or the secondaggregates 322. These active sites, as well as the exposed surfaces ofthe first aggregates 312 and/or the second aggregates 322, mayfacilitate ex-situ electrodeposition prior to incorporation of theelectrode 300 into the battery 100. Electroplating is a process that cancreate a lithium layer 330 (including lithium on exposed surfaces of thehost structure 328) through chemical reduction of metal cations byapplication and/or modulation of an electric current. In implementationsfor which the electrode 300 serves as the anode 120 of the battery 100in FIG. 1, the host structure 328 may be electroplated such that thelithium layer 330 has a thickness between approximately 1 and 5micrometers (μm), 5 μm and 20 μm, or greater than 20 μm. In someinstances, ex-situ electrodeposition may be performed at a locationseparate from the battery 100 prior to the assembly of the battery 100.

In various implementations, excess lithium provided by the lithium layer330 may increase the number of lithium ions 125 available for transportin the battery 100, thereby increasing the storage capacity, longevity,and performance of the battery 100 (as compared with traditionallithium-ion and/or lithium-sulfur batteries).

In some aspects, the lithium layer 330 may produce lithium-intercalatedgraphite (LiC₆) and/or lithiated graphite based on chemical reactionswith the first aggregates 312 and/or the second aggregates 322. Lithiumintercalated between alternating graphene layers may migrate or betransported within the electrode 300 due to differences inelectrochemical gradients during operational cycling of the battery 100,which in turn may increase the energy storage and power delivery of thebattery 100.

FIG. 4 shows a diagram of a portion of an example battery 400 thatincludes a protective lattice 402, according to some implementations. Insome implementations, the protective lattice 402 may be disposed on theanode 220 of the battery 200. In other implementations, the protectivelattice 402 may be disposed on the cathode 210 of the battery 200 (orother suitable batteries). In some aspects, the protective lattice 402may be one example of the protective lattice 280 of FIG. 2. Theprotective lattice 402 may function with many components (e.g., anode,cathode, current collectors associated, carbonaceous materials,electrolyte, and separator) in a manner similar to the battery 100 ofFIG. 1 and/or the battery 200 of FIG. 2.

The protective lattice 402 may include a tri-functional epoxy compoundand a diamine oligomer-based compound that can chemically react witheach other to produce a 3D lattice structure (e.g., as shown in FIG. 6and FIG. 8). In some aspects, the protective lattice 402 may preventpolysulfide migration within the battery 400 by providing nitrogen andoxygen atoms that can chemically bind with lithium present in thepolysulfides, thereby impeding the migration of polysulfides through theelectrolyte 130. As a result, lithium ions 125 can be more freelytransported from the anode 120 and the cathode 110 of FIG. 1, therebyincreasing battery performance metrics.

Cyclical usage of the cathode 110 may cause the formation of cracks 404that at least partially extend into the cathode 110. In oneimplementation, the protective lattice 402 may disperse throughout thecracks 404, thereby reducing susceptibility of the cathode 110 torupture during volumetric expansion of the cathode 110 caused by theretention of polysulfides within the cathode 110 during cyclical usage.In one implementation, the protective lattice 402 of FIG. 4 may have across-linked, 3D structure based on chemical reactions betweendi-functional, or higher functionality Epoxy and Amine or Amidecompounds. For example, the di-functional, or higher functionality Epoxycompound may be trimethylolpropane triglycidyl ether (TMPTE),tris(4-hydroxyphenyl)methane triglycidyl ether, or tris(2,3-epoxypropyl)isocyanurate, and di-functional, or higher functionality Amine compoundmay be dihydrazide sulfoxide (DHSO) or one of polyetheramines, forexample JEFFAMINE® D-230 characterized by repeating oxypropylene unitsin the backbone.

In various implementations, the chemical compounds may be combined andreacted with each other in any number of quantities, amounts, ratiosand/or compositions to achieve different performance capabilitiesrelating to binding with polysulfides generated during operation of thehost battery 400. For example, in one implementation, 113 mg of TMPTEand 134 mg of JEFFAMINE® D-230 polyetheramine may be mixed together anddiluted with 1 mL to 10 mL of tetrahydrofuran (THF), or any othersolvent. Additional amounts of TMPTE and/or JEFFAMINE may be mixedtogether and diluted in THF, or any other solvent, at an example ratioof 113 mg of TMPTE for every 134 mg of JEFFAMINE® D-230 polyetheramine.For this implementation, proof-of-concept (POC) data shows that theprotective lattice 402 of FIG. 4 has a defined weight of approximately2.6 wt. % of the cathode 110 of FIG. 1 or the cathode 210 of FIG. 2. Inother implementations, the protective lattice 402 may have a weight ofapproximately 2 wt. % to 21 wt. % of the cathode 110 and/or the cathode210, where an impedance increases of the cathode 110 and/or the cathode210 may be expected at a weight level of approximately 10 wt. % or morefor the protective lattice 402.

In various implementations, the protective lattice 402 may be fabricatedbased on a mole and/or molar ratio of —NH₂ group and epoxy groups andmay further accommodate various forms of cross-linking betweendi-functional, or higher functionality Epoxy and Amine or Amidecompound. In some aspects, such forms of cross-linking may include afully cross-linked stage, e.g., where one —NH₂ group is chemicallybonded with two epoxy groups and may further extend to configurationsincluding one NH₂ group chemically bonded with only one epoxy group.Still further, in one or more implementations, mixtures including excessquantities (above the ratios presented here) of —NH₂ groups may beprepared to provide additional polysulfide binding capability for theprotective lattice 402.

In some other implementations, the protective lattice 402 may beprepared by mixing 201 g of TMPTE with between 109 g and 283 g ofJEFFAMINE® D-230 polyetheramine. The resulting mixture may be thendiluted with 1 L to 20 L of a selected solvent (such as THF). Theresultant diluted solution may be deposited and/or otherwise disposed onthe cathode 110 to achieve a crosslinker content between 1 wt. % to 10wt. %. Additional TMPTE and/or JEFFAMINE may be mixed together anddiluted in THF, or another suitable solvent, at an example ratio of 201g of TMPTE for every 109 g to 283 g of JEFFAMINE® D-230 polyetheramine.

In still other implementations, the protective lattice 402 may beprepared by mixing 201 g of TMPTE with between 74 g and 278 g DHSO. Theresulting mixture may be then diluted with 1 L to 20 L of a selectedsolvent (such as THF). The resultant diluted solution may be depositedand/or otherwise disposed on the cathode 110 to achieve a crosslinkercontent between 1 wt. % to 10 wt. %. Additional TMPTE and/or JEFFAMINEmay be mixed together and diluted in THF, or another suitable solvent,at an example ratio of 201 g of TMPTE for every 201 g to 278 g ofJEFFAMINE® D-230 polyetheramine.

In one implementation, di-functional, or higher functionality Epoxycompound may chemically react with di-functional, or higherfunctionality amine compound to produce the protective lattice 402 in a3D cross-linked form, which may include both functional epoxy compoundsand amine containing molecules. In some aspects, the protective lattice402, when deposited on the cathode 110 of FIG. 1 or the cathode 210 ofFIG. 2, may have a thickness between approximately 1 nm and 5 μm.

In some implementations, the protective lattice 402 may increase thestructural integrity of the cathode 110 or the cathode 210, may reducesurface roughness, and may retain polysulfides in the cathode. Forexample, in one implementation, the protective lattice 402 may serve assheath on exposed surfaces of the cathode and bind with polysulfides toprevent their migration and diffusion into the electrolyte 130. In thisway, aspects of the subject matter disclosed herein may prevent (or atleast reduce) battery capacity decay by suppressing the polysulfideshuttle effect. In some aspects, the protective lattice 402 may alsofill the cracks 404 formed in the cathode of FIG. 4 to improve cathodecoating integrity. In various implementations, the protective lattice402 may be prepared by drop casting processes in the presence of asolvent, where the resultant solution can penetrate in cracks 404 of thecathode 110 and bind with polysulfides in the cathode 110 to preventtheir migration and/or diffusion throughout the electrolyte 130.

In various implementations, the protective lattice 402 may providenitrogen atoms and/or oxygen atoms that can chemically bond with lithiumin the polysulfides generated during operational battery cycling. In oneexample, the polysulfides may bond with available nitrogen atomsprovided by, for example, DHSO. In another example, the polysulfides maybond with available oxygen atoms provided by, for example, DHSO. In yetanother example, the polysulfides may bond with other available oxygenatoms.

In some other implementations, the recipes described above may bealtered by replacing TMPTE with a tris(4-hydroxyphenyl)methanetriglycidyl ether 910 and/or a tris(2,3-epoxypropyl) isocyanurate. Invarious implementations, the di-amine oligomer-based compound may be (ormay include) a JEFFAMINE® D-230, or other polyetheramines containingpolyether backbone normally based on either propylene oxide (PO),ethylene oxide (EO), or mixed PO/EO structure, for example JEFFAMINE®D-400, JEFFAMINE® T-403. The protective lattice 402 may also includevarious concentration levels of inert molecules, e.g., polyethyleneglycol chains of various lengths, which may allow to fine-tunemechanical properties of protective lattice and the chemical bonding ofvarious atoms to lithium present in the polysulfides.

FIG. 5 shows a diagram of an anode structure 500 that includes a tinfluoride (SnF₂) layer, according to some implementations. Specifically,the diagram depicts a cut-away schematic view of the anode structure 500in which all of the components associated with a first region A haveidentical counterparts in a second region B, where the first and secondregions A and B have opposite orientations around a current collector520. As such, the description below with reference to the components offirst region A is equally applicable to the components of second regionB. In some aspects, the anode 502 may be one example of the anode 120 ofFIG. 1 and/or the anode 220 of FIG. 2.

As discussed, lithium-sulfur batteries, such as the battery 100 of FIG.1 and the battery 200 of FIG. 2, operate as conversion-chemistry typeelectrochemical cells in that sulfur pre-loaded into the cathode maydissolve rapidly into the electrolyte prior to and during operation.Lithium, which may be provided by lithiated anodes and/or may beprevalent in the electrolyte, dissociates into lithium ions (Li+)suitable for transport from the anode to the cathode through theelectrolyte. The production of lithium ions is associated with acorresponding release of electrons, which may flow through an externalcircuit to power a load, as described with reference to FIG. 1. However,when lithium disassociates into lithium ions and electrons, some of thelithium ions may undesirably react with polysulfides produced in thecathode, and therefore may no longer be available to generate an outputcurrent or voltage. This consumption of lithium ions by polysulfidesreduces the overall capacity of the host cell or battery, and may alsofacilitate corrosion of the anode, which can result in cell failure.

In some implementations, the protective layer 516 may be provided aspassivation coating that can reduce the chemical reactivity of the anode502 during cell assembly or formation. In some aspects, the protectivelayer 516 may be permeable to lithium ions while concurrently protectingthe anode 502 from corrosion caused by chemical reactions betweenlithium ions and polysulfides. In other implementations, the protectivelayer 516 may be an artificial solid-electrolyte interphase (A-SEI) thatcan replace naturally occurring SEIs and/or other types of conventionalA-SEIs. In various implementations, the protective layer 516 may bedeposited as a liner on top of one or more films disposed on the anode502. In some aspects, the protective layer 516 may be a self-generatinglayer that forms during electrochemical reactions associated withoperational cycling of the battery. In some aspects, the protectivelayer 516 may have a thickness that is less than 5 microns. In otheraspects, the protective layer 516 may have a thickness between 0.1 and1.0 microns.

In various implementations, one or more engineered additives that mayfacilitate the formation and/or deposition of the protective layer 516on the anode 502 may be provided within the electrolyte of the battery.In other implementations, the engineered additives may be an activeingredient of the protective layer 516. In some aspects, the protectivelayer 516 may provide tin ions and/or fluoride ions that can preventundesirable lithium growths from a first edge 518 ₁ and a second edge518 ₂ of the anode.

A graded layer 514 may be formed and/or deposited onto the anode 502beneath the protective layer 516. In various implementations, the gradedlayer 514 may prevent lithium contained in or associated with the anode502 from participating in undesirable chemical interactions and/orreactions with the electrolyte 540 that can lead to the growth oflithium-containing dendrites from the anode 502. The graded layer 514may also facilitate the production of lithium fluoride based on chemicalreactions between dissociated lithium ions and fluoride ions. Asdiscussed, the presence of lithium fluoride in or near the anode 502 candecrease the polysulfide shuttle effect. For example, formation oflithium fluoride (e.g., form available lithium ions and fluorine ions)may occur uniformly across the entirety of the first edge 518 ₁ and/orthe second edge 518 ₂ of the anode. In this way, localized regions ofhigh lithium concentration in the electrolyte 540 near the anode 502 aresubstantially inhibited. As a result, lithium-lithium bonds contributingto the formation of lithium containing dendritic structures extendinglength-wise from the anode are correspondingly inhibited, therebyyielding free passage of lithium ions from the anode 502 into theelectrolyte (e.g., as encountered during battery operational cycling).In some aspects, the uniform distribution of lithium throughout thegraded layer 514 can increase a uniformity of a lithium-ion flux duringbattery operational cycling. In some aspects, the graded layer 514 maybe approximately 5 nanometers (nm) in thickness.

In one or more implementations, the graded layer 514 may structurallyreinforce the host battery in a manner that not only decreases orprevents lithium-containing dendritic growth from the anode 502 but alsoincreases the ability of the anode 502 to expand and contract duringoperational cycling of the host battery without rupturing. In someaspects, the graded layer 514 has a 3D architecture with a gradedconcentration gradient (e.g., of one or more formative materials and/oringredients including carbon, tin, and/or fluorine), which facilitatesrapid lithium-ion transport. As a result, the graded layer 514 markedlyimproves overall battery efficiency and performance.

In some implementations, the graded layer 514 may provide anelectrochemically desirable surface upon which the protective layer 516may be grown or deposited. For example, in some aspects, the gradedlayer 514 may include compounds and/or organometallic compoundsincluding (but not limited to) aluminum, gallium, indium, nickel, zinc,chromium, vanadium, titanium, and/or other metals. In other aspects, thegraded layer 514 may include oxides, carbides and/or nitrides ofaluminum, gallium, indium, nickel, zinc, chromium, vanadium, titanium,and/or other metals.

In some implementations, the graded layer 514 may include carbonaceousmaterials including (but not limited to) flaky graphene, few layergraphene (FLG), carbon nano onions (CNOs), graphene nanoplatelets, orcarbon nanotubes (CNTs). In other implementations, the graded layer 514may include carbon, oxygen, hydrogen, tin, fluorine and/or othersuitable chemical compounds and/or molecules derived from tin fluorideand one or more carbonaceous materials. The graded layer 514 may beprepared and/or deposited either directly or indirectly on the anode 502at a different concentration levels. For example, the graded layer 514may include 5 wt. % carbonaceous materials with a balance of 95 wt. %tin fluoride, which may result in a relatively uniform disassociation offluorine atoms and/or fluoride ions from the tin fluoride.

Other suitable ratios include: 5% carbonaceous materials with 95% tinfluoride; 10% carbonaceous materials with 90% tin fluoride, 15%carbonaceous materials with 85% tin fluoride, 20% carbonaceous materialswith 80% tin fluoride, 25% carbonaceous materials with 75% tin fluoride,30% carbonaceous materials with 70% tin fluoride, 35% carbonaceousmaterials with 65% tin fluoride, 40% carbonaceous materials with 60% tinfluoride, 45% carbonaceous materials with 55% tin fluoride, 50%carbonaceous materials with 50% tin fluoride, 55% carbonaceous materialswith 45% tin fluoride, 55% carbonaceous materials with 45% tin fluoride,60% carbonaceous materials with 40% tin fluoride, 65% carbonaceousmaterials with 35% tin fluoride, 70% carbonaceous materials with 30% tinfluoride, 75% carbonaceous materials with 25% tin fluoride, 80%carbonaceous materials with 20% tin fluoride, 85% carbonaceous materialswith 15% tin fluoride, 90% carbonaceous materials with 10% tin fluoride,95% carbonaceous materials with 5% tin fluoride. The fluorine atomsand/or fluoride ions may then uniformly react and combine with lithiumions to form lithium fluoride, as further discussed below.

In some implementations, lithium ions cycling between the anode 502 andthe cathode (not shown in FIG. 5) may produce a tin-lithium alloy region512 within the graded layer 514. In some aspects, operational cycling ofthe host battery may result in a uniform dispersion of lithium fluoridewithin the tin-lithium alloy region 512. The uniform dispersion oflithium fluoride may facilitate a defluorination reaction of at leastsome of the tin fluoride within the tin fluoride layer 510 (andadditional tin fluoride which may have dispersed into the graded layer514 and/or the protective layer). The fluorine atoms and/or fluorideions made available by the defluorination reaction may chemically bondwith at least some of the lithium ions present in or near the anode 502,thereby preventing at least some of the lithium ions from bonding witheach other and creating a lithium dendritic growth from the anode 502.

For example, at least a portion of the fluorine atoms and/or fluorideions present in the tin fluoride may dissociate from the protectivelayer 516 and produce tin ions (Sn²⁺) and fluorine ions (2F⁻) via one ormore chemical reactions. The fluorine atoms and/or fluoride ionsdissociated from the protective layer 516 may chemically bond to atleast some of the lithium ions present in the electrolyte 540 and/ordispersed throughout the protective layer 516 or the graded layer 514.In some aspects, the dissociated fluorine atoms may form Li—F bonds orLi—F compounds in the tin-lithium alloy region 512. In other aspects,the dissociated fluorine atoms may form a lithium fluoride layer 510within the graded layer 514.

In addition, in one implementation, at least some of the defluorinatedtin fluoride may disperse uniformly throughout the graded layer 514 toproduce lithium fluoride (LiF) crystals. The lithium fluoride crystalsmay act as an electrical insulator and prevent the flow of electronsfrom the anode 502 into the electrolyte 540 through the first edge 518 ₁and/or the second edge 518 ₂ of the anode 502.

In various implementations, the graded layer 514 may be deposited on theanode 502 by one or more of atomic layer deposition (ALD), chemicalvapor deposition (CVD), or physical vapor deposition (PVD). For example,ALD may be used to deposit protective films on the anode 502 such as,for example, an ALD film that at least partially reacts with theelectrolyte 540 during high-pressure bonding processes. Accordingly, theALD film may be used to produce the protective layer 516 or the gradedlayer 514 using an atomic plane available for lithium transfer. Suchlithium transfer may be similar in principle to that observed for fewlayer graphene (FLG) or graphite, where alternating graphene layers inFLG or graphite intercalate lithium ions in various forms including aslithium titanium oxide (LTO), lithium iron phosphate (PO₃) (LFP). Thedescribed forms of intercalated lithium, e.g., LTO and/or LFP, may beoriented to facilitate rapid lithium atom and/or lithium ion transportand/or diffusion, which may be conducive for the formation and/orsynthesis of lithium fluoride (e.g., in the lithium fluoride layer 510and/or elsewhere), as described earlier. Additional forms ofintercalated lithium, e.g., perovskite lithium lanthanum titanate(LLTO), may also function to store lithium within the anode 502.

In some implementations, the graded layer 514 may include variousdistinct types and/or forms of carbon and/or carbonaceous materials,each having one or more physical attributes that can be selected orconfigured to adjust the reactivity of carbon with contaminants (such aspolysulfides) present in the electrolyte 540 and/or the anode 502. Insome aspects, the selectable physical attributes may include (but arenot limited to) porosity, surface area, surface functionalization, orelectric conductivity. In addition, the graded layer 514 may includebinders or other additives that can be used to adjust one or morephysical attributes of the carbonaceous materials to achieve a desiredreactivity of carbon supplied by the carbonaceous materials withpolysulfides present in the electrolyte 540 and/or the anode 502.

In one implementation, carbonaceous materials within the graded layer514 may capture unwanted contaminants and thereby prevent thecontaminants from chemically reacting with lithium available at exposedsurfaces of the anode 502. Instead, the unwanted contaminants (e.g.,polysulfides) may chemically react with various exposed surfaces of thecarbonaceous materials within the graded layer 514 (e.g., throughcarbon-lithium interactions). In some implementations, the carbonaceousmaterials within the graded layer 514 may cohere to the availablelithium. The degree of cohesion between the carbonaceous materials andthe lithium ions may be selected or modified via chemical reactionsinduced during preparation of the graded layer 514.

In some implementations, various carbon allotropes may be incorporatedwithin the graded layer 514 (such as in one or more portions of thetin-lithium alloy region 512 and/or the tin lithium fluoride layer 510).These carbon allotropes may be functionalized with one or more reactantsand used to form a sealant layer and/or region at an interface of carbonnanodiamonds within the graded layer 514 and the electrolyte 540. Insome aspects, the carbon nanodiamonds may increase the mechanicalrobustness of the anode 502 and/or the graded layer 514. In otheraspects, the carbon nanodiamonds may also provide exposed carbonaceoussurfaces that may be used to decrease the polysulfide shuttle effect bymicro-confining and/or bonding with polysulfides present in theelectrolyte 540 in a manner that retains the polysulfides within definedregions of the battery external to the anode 502.

Alternatively, in other implementations, the carbon nanodiamonds withinthe graded layer 514 may be replaced with carbons and/or carbonaceousmaterials including surfaces and/or regions having a specific LAdimensions (e.g., sp² hybridized carbon), reduced graphene oxide (rGO),and/or graphene. In some aspects, employing the carbonaceous materialsdisclosed herein within a battery may increase carbon stacking and layerformation within the graded layer 514. Exfoliated and oxidizedcarbonaceous materials may also yield more uniform layered structureswithin the graded layer 514 (as compared to carbonaceous materials thathave not been exfoliated and oxidized). In some aspects, solvents suchas tetrabutylammonium hydroxide (TBA) and/or dimethyl formamide (DMF)treatments may be applied to the carbonaceous materials disclosed hereinto increase the wetting of exposed carbonaceous surfaces within thegraded layer 514.

In some implementations, slurries used to form the graded layer 514 maybe doped to improve or otherwise influence the crystalline structure ofcarbonaceous materials within the graded layer 514. For example,addition of certain dopants may influence the crystalline structure ofthe carbonaceous materials in a certain corresponding way, andfunctional groups may be added (e.g., via grafting onto exposed carbonatoms within the carbonaceous materials) within the graded layer 514.

In some implementations, carbonaceous materials having exposed surfacesfunctionalized with one or more of fluorine-containing orsilicon-containing functional groups may be included within the gradedlayer 514. In other implementations, carbonaceous materials havingexposed surfaces functionalized with one or more of fluorine-containingor silicon-containing functional groups may be deposited beneath thegraded layer 514 to form a stable SEI on at an interface between thegraded layer 514 and the anode 502. In one implementation, the stableSEI may replace the protective layer 516. In some implementations, thegraded layer 514 may be slurry cast and/or deposited using othertechniques onto the anode 502 with lithium and carbon interphases, anyof which may be functionalized with silicon and/or nitrogen to inhibitthe diffusion and migration of polysulfides towards exposed surfaces ofthe anode 502. In addition, specific polymers and/or crosslinkers may beincorporated within the graded layer 514 to mechanically strengthen thegraded layer 514, to improve lithium ion transport across the gradedlayer 514, or to increase the uniformity of lithium ion flux across thegraded layer 514. Example polymers and/or polymeric materials suitablefor incorporation within the graded layer 514 may include poly(ethyleneoxide) and poly(ethyleneimine). Example crosslinkers suitable forincorporation within the graded layer 514 may include inorganic linkers(e.g., borate, aluminate, silicate), multifunctional organic molecules(e.g., diamines, diols), polyurea, or high molecular weight (MW)(e.g., >10,000 daltons) carboxymethyl cellulose (CMC).

Various fabrication methods may be employed to produce the graded layer514. In one implementation, direct coating of the interface between theanode 502 and the electrolyte 540 prior to the deposition and/orformation of the graded layer 514 may be performed with a dispersion ofcarbonaceous materials and other chemicals dissolved in a carrier (e.g.,a solvent, binder, polymer). In another implementation, deposition ofthe graded layer 514 may be performed as a separate operation, or may beadded to various other active ingredients (e.g., metals, carbonaceousmaterials, tin fluoride and/or the like) into a slurry that can be castonto the anode 502. Alternatively, in another implementation, theprotective layer 516 may be transferred directly onto the anode 502 by acalendar roll lamination processes. The protective layer 516 and/or thegraded layer 514 may also incorporate partially-cured lithium ionconductive epoxies to, for example, increase adhesion with lithiumbetter during the calendar roll lamination processes.

In one implementation, a carbon-inclusive layered structure (not shownin FIG. 5) may be disposed on the anode 502 as a replacement for thegraded layer 514. The carbon-inclusive layered structure may include anatomic plane available for lithium transfer, and may uniformly transportlithium ions provided by the electrolyte 540 throughout the protectivelayer 516 in a manner that can guide the formation of lithium fluoridein various portions of the battery. In various implementations, thecarbon-inclusive layered structure may include one or more arrangementsof few layer graphene (FLG) or graphite and/or may intercalate withlithium and produce one or more reaction products including lithium tinoxide (LTO), lithium iron phosphate (LFP), or perovskite lithiumlanthanum titanate (LLTO).

In some implementations, the lithium fluoride layer 510 may function asa protection layer against corrosion, including corrosion ofcopper-inclusive surfaces and/or regions of the protective layer 516,the graded layer 514, or the anode 502. In some aspects, the lithiumfluoride layer 510 may also provide a uniform seed layer suitable forlithium deposition, and thereby inhibiting dendrite formation. Inaddition, in some implementations, the lithium fluoride layer 510 mayinclude one or more lithium ion intercalating compounds, any one or morehaving a low voltage penalty. Suitable lithium ion intercalatingcompounds may include graphitic carbon (e.g., graphite, graphene,reduced graphene oxide, rGO). In one implementation, during fabricationof the anode 502, lithium ions may tend to intercalate prior to platingonto exposed carbonaceous surfaces within the lithium fluoride layer510. In this way, the lithium fluoride layer 510 will have a uniform Lidistribution ready to act as a seed layer prior to initiation of lithiumplating and/or electroplating operations.

In one implementation, one or more conformal coatings may be appliedover portions of the anode 502 such that the resulting conformal coatingcontacts and conforms to the first edge 518 ₁ and/or the second edge 518₂ of the anode 502. In some aspects, the conformal coating may begin asa first spacer edge protection region 530 ₁ and a second spacer edgeprotection region 530 ₂ that react or otherwise combine with one or moreof the protective layer 516, the tin-lithium alloy region 512, and/orthe lithium fluoride layer 510 to form a conformal coating 544 that atleast partially seals and protects surfaces and/or interfaces betweenlithium in the anode 502 and various substances suspended in theelectrolyte, e.g., copper (Cu). In some aspects, the dissociation offluorine atoms from tin fluoride present in the conformal coating 544may react with lithium in the anode 502 to form lithium fluoride, ratherthan form or grow into lithium dendrites. In this way, the conformalcoating 544 may decrease lithium dendrite formation or growth from theanode 502.

The conformal coating 544 may be deposited or disposed over the anode502 at any number of different thicknesses. In some aspects, theconformal coating 544 may be less than 5 μm thick. In other aspects, theconformal coating 544 may be less than 2 μm thick. In some otheraspects, the conformal coating 544 may be less than 1 μm thick. Thesethickness levels may impede the migration of polysulfides towards theanode 502 during battery cycling, thereby preventing at least some ofthe lithium ions from reacting with the polysulfides. Lithium ions thatdo not react with the polysulfides are available for transport from theanode to the cathode during discharge cycles of the battery.

The conformal coating 544 (as well as the protective layer 516 and thegraded layer 514) can uniquely regulate lithium ion flux toward thefirst edge 518 ₁ and/or the second edge 518 ₂ of the anode 502, andthereby prevent corrosion of the anode 502. Such regulation may functionin a similar manner to gate spacers used during the fabrication ofpolysilicon (poly-Si) gates. Specifically, gate spacer or gate sidewallconstructs may be used to protect and mechanically support polysilicongates during the fabrication of integrated circuits (ICs). Similarly,edge protection provided by the conformal coating 544 for the anode 502of FIG. 5 regulates lithium ion flux toward the first edge 518 ₁ and/orthe second edge 518 ₂ of the anode 502, and thereby prevents corrosionof the anode 502. This type of edge protection provided by the conformalcoating 544 for the anode 502 may equally apply to other battery and/orelectrical cell formats and/or configurations such as (but not limitedto) cylindrical cells, stacked cells, and/or the like, with variousconstructs engineered specifically to fit within the parameters of eachof these designs.

In some implementations, fabrication and/or deposition of the conformalcoating 544, the protective layer 516, and/or the graded layer 514 onthe anode 502 may depend on the type of battery or cell construct inwhich the anode 502 is incorporated, e.g., cylindrical cells compared topouch cells and/or prismatic cells. In one implementation, forcylindrical cells, metal anodes may be constructed from an electroactivematerial, typically metallic lithium, and/or lithium-containing alloys,such as graphitic and/or other carbonaceous composited includinglithium, as well as any plenary uniform or multi-layer sheet ofmaterial. In one example, a solid metal lithium foil used as the anode502 may be attached to a copper substrate used as the current collector520 to facilitate electron transfer through a tab 546 to an externalload, as depicted in the example of FIG. 5. In other implementations,the battery 500 may include the anode 502 without the current collector520, where carbonaceous materials contained within the anode 502 mayprovide an electrically conductive medium coupled to a circuit.

In some implementations, the anode structure 500 may be incorporatedinto electrochemical cells and/or batteries by winding around a mandrel.Cylindrical cell layouts typically use double-sided anodes, such as theanode structure 500. In some implementations, cylindrical cellconstructions employing the anode structure 500 may use the conformalcoating 544 to protect the first edge 518 ₁ and/or the second edge 518 ₂of the anode 502. The uniform protection provided by the conformalcoating 544 may be referred to herein as “edge protection.” In oneimplementation, edge protection can be incorporated into a cellemploying the anode structure 500 by extending the size and/or area ofthe protective layer 516 to overlap beyond any geometrically inducededge effects, e.g., surface roughness, of the anode.

In other implementations, the anode structure 500 may be incorporatedinto pouch cells and/or prismatic cells. Generally, two constructs ofpouch and/or prismatic cells may be manufactured, including (1):jelly-roll type cells (e.g., seen in industry as lithium-polymerbatteries), two mandrel wound electrodes may be produced in a mannersimilar to cylindrical cells as discussed earlier; and (2): stackedplate type cells, which may be cut from a sheet of a pre-cast and/orpre-laminated prepared anode, leaving an unprotected edge of, forexample, the anode 502 (when prepared in a stacked-plate typeconfiguration) exposed and vulnerable to corrosion, fast ion fluxes andexposure within the cells. The conformal coating 544, in a stacked-platetype configuration, may protect the anode 502 and prevent lithiumover-saturation in the electrolyte 540. In this way, the conformalcoating 544 can control lithium plating on the anode 502 duringoperational cycling of the battery.

In some implementations, one or more chemical reactions may occurbetween the electrolyte 540 and the anode 502 (involving solventdecomposition and/or additive reactions) during cell assembly or cellrest period. These chemical reactions may assist in the production ofthe conformal coating 544. In some aspects, elevated and/or reducedtemperatures (e.g., relative to room temperature and/or 20° C.) may beused as a stimulus for lithium-induced polymerization of the conformalcoating 544. For example, the lithium-induced polymerization may occurin the presence of one or more catalysts and/or by using lithium metal,and its associated chemical reactivity, as an inducing agent to initiatefree-radical based polymerization of constituent species within any oneor more layers of the anode structure 500 and/or the conformal coating544. In addition, electrochemical reactions under electrical bias ineither the forward or reverse direction may be used to fabricate and/ordeposit the conformal coating 544 onto the anode 502, as well as usageof secondary metals and/or salts as additives that may decompose to forman alloy on the first edge 518 ₁ and/or the second edge 518 ₂ ofmetallic lithium in the anode 502 exposed to the electrolyte 540. Forexample, suitable additives may contain one or more metallic species,e.g., desired for co-alloying with lithium or to be used as a blockinglayer to reduce lithium transfer to the first edge 518 ₁ and/or thesecond edge 518 ₂ of the anode 502.

FIG. 6 shows a schematic diagram of an enlarged portion 600 of the anodestructure 500 of FIG. 5, according to some implementations. The enlargedportion 600 illustrates placement of the first spacer edge protectionregion 530 ₁ and the second spacer edge protection region 530 ₂(collectively referred to as the edge protection region 530 in FIG. 6)in a direction orthogonal to the first edge 518 ₁ and/or the second edge518 ₂, as shown in FIG. 5. As a result, the edge protection region 530,which may include various carbonaceous materials 610 organized intostructures and/or lattices, may block lithium ions from undesirablyescaping the anode 502 across the edge protection region 530. In thisway, lithium ion dissociation, flux, transport, and/or other movementmay be channeled effectively throughout the enlarged portion 600 of FIG.6 (as well as the anode structure 500 of FIG. 5), thereby yieldingoptimal battery operational cycling. In some implementations,carbonaceous materials 610 used to produce the edge protection regionmay include few layer graphene (FLG), multi-layer graphene (MLG),graphite, carbon nano-tubes (CNTs), carbon nano-onions (CNOs) and/or thelike. The carbonaceous materials 610 (e.g., shown in FIG. 8A, FIG. 8B,FIG. 9 and/or FIG. 10) may be synthesized, self-nucleated, or otherwisejoined together at varying concentration levels to provide for completetunability of the edge protection region 530. For example, the density,thickness, and/or compositions of may be designed to reduce lithium ionpermeation more than the protective layer 516 or the graded layer 514 todirect lithium ion permeation accordingly. In some implementations, theedge protection region 530 may be less than 5 μm thick. In otheraspects, the edge protection region 530 may be less than 2 μm thick. Insome other aspects, the edge protection region 530 may be less than 1 μmthick. In some implementations, a conductive additive 640 may be addedto the carbonaceous materials 610, as well as a binder 620.

FIG. 7 shows a diagram of a polymeric network 710, according to someimplementations. In some aspects, the polymeric network 710 may be oneexample of the polymeric network 285 of FIG. 2. The polymeric network710 may be disposed on an anode 702. The anode 702 may be formed as analkali metal layer having one or more exposed surfaces that include anynumber of alkali metal-containing nanostructures or microstructures. Thealkali metal may include (but is not limited to) lithium, sodium, zinc,indium and/or gallium. The anode 710 may release alkali ions duringoperational cycling of the battery.

A layer 714 of carbonaceous materials may be grafted with fluorinatedpolymer chains and deposited over one or more exposed surfaces of theanode 702. The grafting may be based on (e.g., initiated by) activationof carbonaceous material with one or more radical initiators, forexample, benzoyl peroxide (BPO) or azobisisobutyronitrile (AIBN),followed by reaction with monomer molecules. The polymeric network 710may be based on the fluorinated polymer chains cross-linked with oneanother and carbonaceous materials of the layer 714 such that the layer714 is consumed during generation of the polymeric network 710. In someimplementations, the polymeric network 710 may have a thicknessapproximately between 0.001 μm and 5 μm and include betweenapproximately 0.001 wt. % to 2 wt. % of the fluorinated polymer chains.In some other implementations, the cross-linked polymeric network 710may include between approximately 5 wt. % to 100 wt. % of the pluralityof carbonaceous materials grafted with fluorinated polymer chains and abalance of fluorinated polymers, or one or more non-fluorinatedpolymers, or one or more cross-linkable monomers, or combinationsthereof. In one implementation, carbonaceous materials grafted withfluorinated polymer chains may include 5 wt. % to 50 wt. % offluorinated polymer chains and a balance of carbonaceous material.

During battery cycling, carbon-fluorine bonds within the polymericnetwork 710 may chemically react with newly forming Lithium metal andconvert into carbon-Lithium bonds (C—Li). These C—Li bonds may, in turn,react with carbon-fluorine bonds within the polymeric network 710 via aWurtz reaction 750, to further cross-link polymeric network by newlyformed C—C bonds and to form an alkali-metal containing fluoride (suchas lithium fluoride (LiF)). Additional polymeric network cross-linkingleading to uniform formation of the alkali-metal containing fluoride maythereby suppress alkali metal dendrite formation 740 associated with theanode 702, thereby improving battery performance and longevity. In oneimplementation, grafting of fluorinated m/acrylate (FMA) to one or moreexposed graphene surfaces of carbonaceous materials in the layer 714 maybe performed in an organic solution, e.g., leading to the formation ofgraphene-graft-poly-FMA and/or the like. Incorporation ofcarbon-fluorine bonds on exposed graphene surfaces may enable the Wurtzreaction 750 to occur between carbon-fluorine bonds and metallic surfaceof an alkali metal (e.g., lithium) provided by the anode 702. In thisway, completion of the Wurtz reaction 750 may result in the formation ofthe polymeric network 710. In some aspects, the polymeric network 710may include a density gradient 716 pursuant to completion of the Wurtzreaction 750. The density gradient 716 may include interconnectedgraphene flakes and may be infused with one or more metal-fluoride saltsformed in-situ. In addition, layer porosity and/or mechanical propertiesmay be tuned by carbon loading and/or a combination of functionalizedcarbons, each having a unique and/or distinct physical structure.

In some implementations, carbonaceous materials within the densitygradient 716 may include one or more of flat graphene, wrinkledgraphene, a plurality of carbon nano-tubes (CNTs), or a plurality ofcarbon nano-onions (CNOs) (e.g., as depicted in FIG. 8A and/FIG. 8B andas shown in the micrographs of FIG. 9 and FIG. 10). In oneimplementation, graphene nanoplatelets may be dispersed throughout andisolated from each other within the polymeric network 710. Thedispersion of the graphene nanoplatelets includes one or more differentconcentration levels. In one implementation, the dispersion of thegraphene nanoplatelets may include at least some of the carbonaceousmaterials functionalized with at least some of the fluorinated polymerchains.

For example, the fluorinated polymer chains may include one or moreacrylate or methacrylate monomers including2,2,3,3,4,4,5,5,6,6,7,7-Dodecafluoroheptyl acrylate (DFHA),3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorodecyl methacrylate(HDFDMA), 2,2,3,3,4,4,5,5-Octafluoropentyl methacrylate (OFPMA),Tetrafluoropropyl methacrylate (TFPM),3-[3,3,3-Trifluoro-2-hydroxy-2-(trifluoromethyl)propyl]bicyclo[2.2.1]hept-2-ylmethacrylate (HFA monomer), or vinyl-based monomers including2,3,4,5,6-Pentafluorostyrene (PFSt).

In some implementations, fluorinated polymer chains may be grafted to asurface of the layer of carbonaceous materials and may therebychemically interact with the one or more surfaces of the alkali metal ofthe anode via the Wurtz reaction 750. In organic chemistry,organometallic chemistry, and inorganic main-group polymers, the Wurtzreaction is a coupling reaction, whereby two alkyl halides are reactedwith sodium metal (or some other metal) in dry ether solution to form ahigher alkane. In this reaction alkyl halides are treated with alkalimetal, for example, sodium metal in dry ethereal (free from moisture)solution to produce higher alkanes. In case of Sodium intermediateproduct of the Wurtz reaction are highly polar and highly reactiveCarbon-Sodium metal bonds, which in turn are chemically reacting withCarbon-Halide bonds to yield newly formed C—C bonds and Sodium Halide. Aformation of new Carbon-Carbon bonds allows to use the Wurtz reactionfor the preparation of higher alkanes containing even number of carbonatoms, for example:2R—X+2Na→R—R+2Na⁺X⁻  (Eq. 1)

Other metals have also been used to influence Wurtz coupling, among themsilver, zinc, iron, activated copper, indium and a mixture of manganeseand copper chloride. The related reaction dealing with aryl halides iscalled the Wurtz-Fittig reaction. This can be explained by the formationof free radical intermediate and its subsequent disproportionation togive alkene. The Wurtz reaction 750 occurs through a free-radicalmechanism that makes possible side reactions producing alkene products.In some implementations, chemical interactions associated with the Wurtzreaction described above may form an alkali metal fluoride, e.g.,lithium fluoride.

In one implementation, the polymeric network 710 may include aninterface layer 718 in contact with the anode 702. A protective layer720 may be disposed on top of the interface layer 718, which may bebased on the Wurtz reaction 750 at an interface between the anode 702and the polymeric network 710. The interface layer 718 may have arelatively high cross-linking density (e.g., of fluorinated polymersand/or the like), a high metal-fluoride concentration, and a relativelylow carbon-fluorine bond concentration. In contrast to the interfacelayer 718, the protective layer 720 may have a relatively lowcross-linking density, a low metal-fluoride concentration, and a highcarbon-fluorine bond concentration.

In some implementations, the interface layer 718 may includecross-linkable monomers such as methacrylate (MA), acrylate, vinylfunctional groups, or a combination of epoxy and amine functionalgroups. In one implementation, the protective layer 720 may becharacterized by the density gradient 716. In this way, the densitygradient 716 may be associated with one or more self-healing propertiesof the protective layer 720 and/or may strengthen the polymeric network710. In some implementations, the strengthened polymeric network 720 mayfurther suppress alkali metal dendrite formation 740 from the anode 702during battery cycling.

Operationally, the interface layer 718 may suppress alkali metaldendrite formation 740 associated with the anode 702 by uniformlyproducing metal-fluorides, e.g., lithium fluoride, at an interfaceacross the length of the anode 702. The uniform production of metalfluorides causes dendrite surface dissolution, e.g., via conversion intometal-fluorides, ultimately suppressing alkali metal dendrite formation740. In addition, cross-linking of fluorinated polymer chains overremaining dendrites may further suppress alkali metal dendrite formation740. In some implementations, the density gradient 716 may be tuned tocontrol the degree of cross-linking between the fluorinated polymerchains.

FIG. 8A shows a simplified cutaway view of an example carbonaceousparticle 800 with graded porosity, according to some implementations.The carbonaceous particle 800 may be synthesized in a reactor, andoutput in a controlled manner to produce the cathode 110 and/or anode120 of FIG. 1, the cathode 210 and/or anode 220 of FIG. 2, or theelectrode 300 of FIG. 3. The carbonaceous particle 800, which may alsobe referred to as a composition of matter, includes a plurality ofregions nested within each other. Each region may include at least afirst porosity region 811 and a second porosity region 812. The firstporosity region 811 may include a plurality of first pores 801, and thesecond porosity region 812 may include a plurality of second pores 802.In some aspects, each region may be separated from immediate adjacentregions by at least some of the first pores 801. The first pores 801 maybe dispersed throughout the first porosity region 811 of thecarbonaceous particle 800, and the second pores 802 may be dispersedthroughout the second porosity region 812 of the carbonaceous particle800. In this way, the first pores 801 may be associated with a firstpore density, and the second pores 802 may be associated with a secondpore density that is different than the first pore density. In someaspects, the first pore density may be between approximately 0.0 cubiccentimeters (cc)/g and 2.0 cc/g, and the second pore density may bebetween approximately 1.5 and 5.0 cc/g. In some aspects, the first pores801 may be configured to retain polysulfides 820, and the second pores802 may provide exit pathways from the carbonaceous particle 800.

A group of carbonaceous particles 800 may be joined together to form acarbonaceous aggregate (not shown for simplicity), and a group ofcarbonaceous aggregates may be joined together to form a carbonaceousagglomerate (not shown for simplicity). In some implementations, thefirst and second pores 801 and 802 may be dispersed throughoutaggregates formed by respective groups of the carbonaceous particles800. In some aspects, the first porosity region 811 may be at leastpartially encapsulated by the second porosity region 812 such that arespective agglomerate may include some of the first pores 801 and/orsome of the second pores 802.

In some implementations, the carbonaceous particle 800 may have aprincipal dimension “A” in an approximate range between 20 nm and 150nm, an aggregate formed by a group of the carbonaceous particle 800 mayhave a principal dimension in an approximate range between 20 nm and 10μm, and an agglomerate formed by a group of aggregates may have aprincipal dimension in an approximate range between 0.1 μm and 1,000 μm.In some aspects, at least some of the first pores 801 and the secondpores 802 has a principal dimension in an approximate range between 1.3nm and 32.3 nm. In one implementation, each of the first pores 801 has aprincipal dimension in an approximate range between 0 nm and 100 nm.

The carbonaceous particle 800 may also include a plurality of deformableregions 813 distributed along a perimeter 810 of the carbonaceousparticle 800. The carbonaceous particle 800 may conduct electricityalong joined boundaries with (such as the perimeter 810) one or moreother carbonaceous particles. The carbonaceous particle 800 may alsoconfine polysulfides 820 within the first pores 801 and/or at one ormore blocking regions 822, thereby inhibiting the migration ofpolysulfides 820 towards the anode and increasing the rate at whichlithium ions can be transported from the anode to the cathode of a hostbattery.

In some implementations, the carbonaceous particle 800 may have asurface area of exposed carbon surfaces in an approximate range between10 m²/g to 3,000 m²/g. In other implementations, the carbonaceousparticle 800 may have a composite surface area including sulfur 824micro-confined within a number of the first pores 801 and/or a number ofthe second pores 802. As used herein, the first and second pores 801 and802 that micro-confine polysulfides 820 may be referred to as“functional pores.” In some aspects, one or more of the carbonaceousparticles, the aggregates formed by corresponding groups of carbonaceousparticles, or the agglomerates formed by corresponding groups ofaggregates may include one or more exposed carbon surfaces configured tonucleate the sulfur 824. The composite surface area may be in anapproximate range between 10 m²/g to 3,000 m²/g, and the carbonaceousparticle 800 may have a sulfur to carbon weight ratio betweenapproximately 1:5 to 10:1. In some aspects, the carbonaceous particle800 may have an electrical conductivity in an approximate range between100 S/m to 20,000 S/m at a pressure of 12,000 pounds per square in(psi).

In some implementations, the carbonaceous particle 800 may include asurfactant or a polymer that includes one or more of styrene butadienerubber, polyvinylidene fluoride, poly acrylic acid, carboxyl methylcellulose, polyvinylpyrrolidone, and/or polyvinyl acetate that can actas a binder to join a group of the carbonaceous particles 800 together.In other implementations, the carbonaceous particle 800 may include agel-phase electrolyte or a solid-phase electrolyte disposed within atleast some of the pores 801 or 802.

FIG. 8B shows a diagram of an example of a tri-zone particle 850,according to some implementations. In various implementations, thetri-zone particle 850 may be one example of the carbonaceous particle800 of FIG. 8A. The tri-zone particle 850 may include three discretezones such as (but not limited to) a first zone 851, a second zone 852,and a third zone 853. In some aspects, each of the zones 851-853surrounds and/or encapsulates a preceding zone. For example, the firstzone 851 may be surrounded by or encapsulated by the second zone 852,and the second zone 852 may be surrounded by or encapsulated by thethird zone 853. The first zone 851 may correspond to an inner region ofthe particle 850, the second zone 852 may correspond to an intermediatetransition region of the particle 850, and the third zone 853 maycorrespond to an outer region of the particle 850. In some aspects, thetri-zone particle 850 may include a permeable shell 855 that deforms inresponse to contact with one or more adjacent non-tri-zone particlesand/or tri-zone particles 850.

In some implementations, the first zone 851 may have a relatively lowdensity, a relatively low electrical conductivity, and a relatively highporosity, the second zone 852 may have an intermediate density, anintermediate electrical conductivity, and an intermediate porosity, andthe third zone 853 may have a relatively high density, a relatively highelectrical conductivity, and a relatively low porosity. In some aspects,the first zone 851 may have a density of carbonaceous material betweenapproximately 1.5 g/cc and 5.0 g/cc, the second zone 852 may have adensity of carbonaceous material between approximately 0.5 g/cc and 3.0g/cc, and the third zone 853 may have a density of carbonaceous materialbetween approximately 0.0 and 1.5 g/cc. In other aspects, the first zone851 may include pores having a width between approximately 0 and 40 nm,the second zone 852 may include pores having a width betweenapproximately 0 and 35 nm, and the third zone 853 may include poreshaving a width between approximately 0 and 30 nm. In some otherimplementations, the second zone 852 may not be defined for the tri-zoneparticle 850. In one implementation, the first zone 851 may have aprincipal dimension D₁ between approximately 0 nm and 100 nm, the secondzone 852 may have a principal dimension D₂ between approximately 20 nmand 150 nm, and the third zone 853 may have a principal dimension D₃ ofapproximately 200 nm.

Aspects of the present disclosure recognize that the unique layout ofthe tri-zone particle 850 and the relative dimensions, porosities, andelectrical conductivities of the first zone 851, the second zone 852,and the third zone 853 can be selected and/or modified achieve a desiredbalance between minimizing the polysulfide shuttle effect and maximizingthe specific capacity of a host battery. Specifically, in some aspects,the pores may decrease in size and volume from one zone to other. Insome implementations, the tri-zone particle may consist entirely of onezone with a range of pore sizes and pores distributions (e.g., poredensity). For the example of FIG. 8B, the pores 861 associated with thefirst zone 851 or the first porosity region have relatively large widthsand may be defined as macropores, the pores 862 associated with thesecond zone 851 or the second porosity region have intermediate-sizedwidths and may be defined as mesopores, and the pores 863 associatedwith the third zone 853 or the third porosity region have relativelysmall widths and may be defined as micropores.

A group of tri-zone particles 850 may be joined together to form anaggregate (not shown for simplicity), and a group of the aggregates maybe joined together to form an agglomerate (not shown for simplicity). Insome implementations, a plurality of mesopores may be interspersedthroughout the aggregates formed by respective groups of thecarbonaceous particles 800. In some aspects, the first porosity region811 may be at least partially encapsulated by the second porosity region812 such that a respective aggregate may include one or more mesoporesand one or more macropores. In one implementation, each mesopore mayhave a principal dimension between 3.3 nanometers (nm) and 19.3 nm, andeach macropore may have a principal dimension between 0.1 μm and 1,000μm. In some instances, the tri-zone particle 850 may include carbonfragments intertwined with each other and separated from one another byat least some of the mesopores.

In some implementations, the tri-zone particle 850 may include asurfactant or a polymer that includes one or more of styrene butadienerubber, polyvinylidene fluoride, poly acrylic acid, carboxyl methylcellulose, polyvinylpyrrolidone, and/or polyvinyl acetate that can actas a binder to join a group of the carbonaceous materials together. Inother implementations, the tri-zone particle 850 may include a gel-phaseelectrolyte or a solid-phase electrolyte disposed within at least someof the pores.

In some implementations, the tri-zone particle 850 may have a surfacearea of exposed carbonaceous surfaces in an approximate range between 10m²/g to 3,000 m²/g and/or a composite surface area (including sulfurmicro-confined within pores) in an approximate range between 10 m²/g to3,000 m²/g. In one implementation, a composition of matter including amultitude of tri-zone particles 850 may have an electrical conductivityin an approximate range between 100 S/m to 20,000 S/m at a pressure of12,000 pounds per square in (psi) and a sulfur to carbon weight ratiobetween approximately 1:5 to 10:1.

FIG. 8C shows an example step function 800C representative of theaverage pore volumes in each of the regions of the tri-zone particle 850of FIG. 8B, according to some implementations. As discussed, the poresdistributed throughout the tri-zone particle 850 may have differentsizes, volumes, or distributions. In some implementations, the averagepore volume may decrease based on a distance between a center of thetri-zone particle 850 and an adjacent zonae, for example, such thatpores associated with the first zone 851 or the first porosity regionhave a relatively large volume or pore size, pores associated with thesecond zone 852 or the second porosity region have an intermediatevolume, and pores associated with the third zone 853 or the thirdporosity region have a relatively small volume. The interior region hasa higher pore volume than the regions near the periphery. The regionwith higher pore volume provides for high sulfur loading whereas thelower pore volume outer regions mitigate the migration of polysulfidesduring cell cycling. In the example of FIG. 8C, the average pore volumein the inner region is approximately 3 cc/g, the average pore volume inthe outermost region is −0.5 cc/g and the average pore volume in theintermediate region is between 0.5 cc/g and 3 cc/g.

FIG. 8D shows a graph 800D depicting an example distribution of porevolume versus pore width of carbonaceous particles described herein. Asdepicted in the graph 800D, pores associated with a relatively high porevolume may have a relatively low pore width, for example, such that thepore width generally increases as the pore volume decreases. In someaspects, pores having a pore width less than approximately 1.0 nm may bereferred to as micropores, pores having a pore width betweenapproximately 3 and 11 nm may be referred to as mesopores, and poreshaving a pore width greater than approximately 24 nm may be referred toas macropores.

FIG. 9A shows a micrograph 900 of a plurality of carbonaceous structures902, according to some implementations. In some implementations, each ofthe carbonaceous structures 902 may have a substantially hollow a coreregion surrounded by various monolithic carbon growths and/or layering.In some aspects, the monolithic carbon growths and/or layering may beexamples of the monolithic carbon growths and/or layering described withreference to FIGS. 8A and 8B. In some instances, the carbonaceousstructures 902 may include several concentric multi-layered fullerenesand/or similarly shaped carbonaceous structures organized at varyinglevels of density and/or concentration. For example, the actual finalshape, size, and graphene configuration of each of the carbonaceousstructures 902 may depend on various manufacturing processes. Thecarbonaceous structures 902 may, in some aspects, demonstrate poor watersolubility. As such, in some implementations, non-covalentfunctionalization may be utilized to alter one or more dispersibilityproperties of the carbonaceous structures 902 without affecting theintrinsic properties of the underlying carbon nanomaterial. In someaspects, the underlying carbon nanomaterial may be formative a sp²carbon nanomaterial. In some implementations, each of the carbonaceousstructures 902 may have a diameter between approximately 20 and 500 nm.In various implementations, groups of the carbonaceous structures 902may coalesce and/or join together to form aggregates 904. In addition,groups of the aggregates 904 may coalesce and/or join together to formagglomerates 906. In some aspects, one or more of the carbonaceousstructures 902, the aggregates 904, and/or the agglomerates 906 may beused to form the anode and/or the cathode of the battery 100 of FIG. 1,the battery 200 of FIG. 2, or the electrode 300 of FIG. 3.

FIG. 9B shows a micrograph 950 of an aggregate formed of carbonaceousmaterial, according to some implementations. In some implementations,the aggregate 960 may be an example of one of the aggregates 904 of FIG.9. In one implementation, exterior carbonaceous shell-type structures952 may fuse together with carbons provided by other carbonaceousshell-type structures 954 to form a carbonaceous structure 956. A groupof the carbonaceous structures 956 may coalesce and/or join with oneanother to form the aggregate 1010. In some aspects, a core region 958of each of the carbonaceous structures 956 may be tunable, for example,in that the core region 958 may include various defined concentrationlevels of interconnected graphene structures, as described withreference to FIG. 8A and/or FIG. 8B. In some implementations, some ofthe carbonaceous structures 956 may have a first concentration ofinterconnected carbons approximately between 0.1 g/cc and 2.3 g/cc at ornear the exterior carbonaceous structure 952. Each of the carbonaceousstructures 956 may have pores to transport lithium ions extendinginwardly from toward the core region 1008.

In some implementations, the pores in each of the carbonaceousstructures 956 may have a width or dimension between approximately 0.0nm and 0.5 nm, between approximately 0.0 and 0.1 nm, betweenapproximately 0.0 and 6.0 nm, or between approximately 0.0 and 35 nm.Each carbonaceous structures 956 may also have a second concentration ator near the core region 958 that is different than the firstconcentration. For example, the second concentration may include severalrelatively lower-density carbonaceous regions arranged concentrically.In one implementation, the second concentration may be lower than thefirst concentration at between approximately 0.0 g/cc and 1.0 g/cc orbetween approximately 1.0 g/cc and 1.5 g/cc. In some aspects, therelationship between the first concentration and the secondconcentration may be used to achieve a balance between confining sulfuror polysulfides within a respective electrode and maximizing thetransport of lithium ions. For example, sulfur and/or polysulfides maytravel through the first concentration and be at least temporarilyconfined within and/or interspersed throughout the second concentrationduring operational cycling of a lithium-sulfur battery.

In some implementations, at least some of the carbonaceous structures956 may include CNO oxides organized as a monolithic and/orinterconnected growths and be produced in a thermal reactor. Forexample, the carbonaceous structures 956 may be decorated with cobaltnanoparticles according to the following example recipe: cobalt(II)acetate (C₄H₆CoO₄), the cobalt salt of acetic acid (often found astetrahydrate Co(CH₃CO₂)₂.4H₂O, which may be abbreviated asCo(OAc)₂.4H₂O, may be flowed into the thermal reactor at a ratio ofapproximately 59.60 wt % corresponding to 40.40 wt % carbon (referringto carbon in CNO form), resulting in the functionalization of activesites on the CNO oxides with cobalt, showing cobalt-decorated CNOs at a15,000× level, respectively. In some implementations, suitable gasmixtures used to produce Carbon #29 and/or the cobalt-decorated CNOs mayinclude the following steps:

-   -   Ar purge 0.75 standard cubic feet per minute (scfm) for 30 min;    -   Ar purge changed to 0.25 scfm for run;    -   temperature increase: 25° C. to 300° C. 20 mins; and    -   temperature increase: 300°-500° C. 15 mins.

Carbonaceous materials described with reference to FIGS. 9A and 9B mayinclude or otherwise be formed from one or more instances of graphene,which may include a single layer of carbon atoms with each atom bound tothree neighbors in a honeycomb structure. The single layer may be adiscrete material restricted in one dimension, such as within or at asurface of a condensed phase. For example, graphene may grow outwardlyonly in the x and y planes (and not in the z plane). In this way,graphene may be a two-dimensional (2D) material, including one orseveral layers with the atoms in each layer strongly bonded (such as bya plurality of carbon-carbon bonds) to neighboring atoms in the samelayer.

In some implementations, graphene nanoplatelets (e.g., formativestructures included in each of the carbonaceous structures 956) mayinclude multiple instances of graphene, such as a first graphene layer,a second graphene layer, and a third graphene layer, all stacked on topof each other in a vertical direction. Each of the graphenenanoplatelets, which may be referred to as a GNP, may have a thicknessbetween 1 nm and 3 nm, and may have lateral dimensions ranging fromapproximately 100 nm to 100 μm. In some implementations, graphenenanoplatelets may be produced by multiple plasma spray torches arrangedsequentially by roll-to-roll (R2R) production. In some aspects, R2Rproduction may include deposition upon a continuous substrate that isprocessed as a rolled sheet, including transfer of 2D material(s) to aseparate substrate. In some instances, the R2R production may be used toform the first thin film 310 and/or the second thin film 320 of theelectrode 300 of FIG. 3, for example, such that the concentration levelof the first aggregates 312 within the first thin film 310 is differentthan the concentration level of the second aggregates 322 within thesecond thin film 320. That is, the plasma spray torches used in the R2Rprocesses may spray carbonaceous materials at different concentrationlevels to create the first thin film 310 and/or the second thin film 320using specific concentration levels of graphene nanoplatelets.Therefore, R2R processes may provide a fine level of tunability for thebattery 100 of FIG. 1 and/or the battery 200 or FIG. 2.

FIGS. 10A and 10B show transmission electron microscope (TEM) images1000 and 1050, respectively, of carbonaceous particles treated withcarbon dioxide (CO₂), according to some implementations. Thecarbonaceous particles shown in FIGS. 10A and 10B may include orotherwise be formed from one or more instances of graphene, which mayinclude a single layer of carbon atoms with each atom bound to threeneighbors in a honeycomb structure.

FIG. 11 shows a diagram 1100 depicting carbon porosity types of variouscarbonaceous aggregates, according to some implementations. In variousimplementations, the carbonaceous aggregates described with reference toFIG. 11 may be examples of the aggregates 904 of FIG. 9A and/or theaggregates 956 of FIG. 9B. In some aspects, the carbonaceous aggregatesdescribed with reference to FIG. 11 may be used to form the electrode300 of FIG. 3. As discussed, the aggregates may be formed from or mayinclude a group of carbonaceous structures such as the carbonaceousstructure 902 of FIG. 9A or the carbonaceous structures 956 of FIG. 9B.In some aspects, the carbonaceous structures may be CNOs.

The carbonaceous structures may be used to form an electrode (such asthe electrode 300 of FIG. 3) having any of the porosity types shown inthe diagram 1100. For example, the electrode may include any of aporosity type 1 1110, a porosity type II 1120, and a porosity type III1130. In some implementations, the porosity type 1 1110 may include afirst pore 1111, a second pore 1112, and a third pore 1113, all sizedwith a principal dimension of less than 5 nm to retain polysulfideswithin the electrode. Some polysulfides may grow in size upon forminglarger complexes and become immovably lodged within pores of theporosity type I 1110. In some implementations, aggregates may be joinedtogether to create pores of the porosity type II 1120 and/or porositytype III 1130 that can retain larger polysulfides and/or polysulfidecomplexes.

FIG. 12 shows a graph 1200 depicting pore size versus pore distributionof an example electrode, according to some implementations. As usedherein, “Carbon 1” refers to structured carbonaceous materials includingmostly micropores (such as less than 5 nm in principal dimension), and“Carbon 2” refers to structured carbonaceous materials including mostlymesopores (such as between approximately 20 nm to 50 nm in principaldimension). In some implementations, an electrode suitable for use inone of the batteries disclosed herein may be prepared to have the poresize versus pore distribution depicted in the graph 1200.

FIG. 13 shows a first graph 1300 and a second graph 1310 depictingbattery performance per cycle number, according to some implementations.Specifically, the first graph 1300 shows the specific discharge capacityof an example battery employing an electrolyte 1302 disclosed hereinrelative to the specific discharge capacity of a conventional batteryemploying a conventional electrolyte. The second graph shows thecapacity retention of the battery employing the electrolyte 1302relative to the capacity retention of the battery employing theconventional electrolyte. In some aspects, the electrolyte 1302 may beone example of the electrolyte 130 of FIG. 1 or the electrolyte 230 ofFIG. 2. In the first graph 1300 and the second graph 1310, theconventional electrolyte is prepared as 1 M LiTFSI in DME:DOL:TEGDME(volume:volume:volume=1:1:1) with 2 wt. % LiNO₃.

FIG. 14 shows a bar chart 1400 depicting battery performance per cyclenumber, according to some implementations. Specifically, the bar chart1400 depicts the specific discharge capacity per cycle number of anexample battery employing an electrolyte 1402 disclosed herein relativeto the specific discharge capacity per cycle number of a conventionalbattery employing a conventional electrolyte. In some aspects, theelectrolyte 1402 may be one example of the electrolyte 130 of FIG. 1 orthe electrolyte 230 of FIG. 2. In the graph 1400, the conventionalelectrolyte is prepared as 1 M LiTFSI in DME:DOL:TEGDME(volume:volume:volume=1:1:1). The bar chart 1400 shows that employingthe electrolyte 1402 in an example battery (such as the battery 100 ofFIG. 1 or the battery 200 of FIG. 2) may increase the specific dischargecapacity of the battery by approximately 28% at the 3^(rd) cycle number,by approximately 30% at the 50^(th) cycle number, and by approximately39% at the 60^(th) as compared to a battery employing the conventionalelectrolyte.

FIG. 15 shows a first graph 1500 and a second graph 1510 depictingbattery performance per cycle number, according to some implementations.Specifically, the first graph 1500 shows the electrode dischargecapacity per cycle number of an example lithium-sulfur coin cellemploying an electrolyte 1502 disclosed herein relative to the electrodedischarge capacity per cycle number of an example lithium-sulfur coincell battery employing a conventional electrolyte, and the second graph1510 shows the capacity retention per cycle number of the lithium-sulfurcoin cell battery employing the electrolyte 1502 relative to theelectrode discharge capacity per cycle number of the lithium-sulfur coincell battery employing the conventional electrolyte. In some aspects,the electrolyte 1502 may be one example of the electrolyte 130 of FIG. 1or the electrolyte 230 of FIG. 2. The lithium-sulfur coin cell batteryis cycled at a discharge rate of 1C (such as fully discharged within onehour), at 100% depth-of-discharge (DOD) and is kept at approximately atroom temperature (68° F. or 20° C.). The conventional electrolyte isprepared as 1 M LiTFSI in DME:DOL:TEGDME (volume:volume:volume=1:1:1)with 2 wt. % LiNO₃.

FIG. 16 shows a graph 1600 depicting electrode discharge capacity percycle number, according to some implementations. Specifically, the graph1600 depicts the electrode discharge capacity per cycle number of anexample battery employing an electrolyte 1602 disclosed herein relativeto the electrode discharge capacity of a conventional battery employinga conventional electrolyte. In some aspects, the electrolyte 1602 may beone example of the electrolyte 130 of FIG. 1 or the electrolyte 230 ofFIG. 2. The conventional electrolyte is prepared as 1 M LiTFSI inDME:DOL:TEGDME (volume:volume:volume=1:1:1) with 2 wt. % LiNO₃, and theelectrolyte 1602 is prepared as 1 M LiTFSI in DME:DOL:TEGDME(volume:volume:volume=58:29:13) with approximately 2 wt. % LiNO₃.

FIG. 17 shows another graph 1700 depicting electrode discharge capacityper cycle number, according to some implementations. Specifically, thegraph 1700 depicts the electrode discharge capacity per cycle number ofan example battery employing an electrolyte 1702 and solvent package1704 disclosed herein relative to the electrode discharge capacity of aconventional battery employing a conventional electrolyte and solventpackage. The conventional electrolyte is prepared as 1 M LiTFSI inDME:DOL:TEGDME (volume:volume:volume=1:1:1) with approximately 2 wt. %LiNO₃, and the electrolyte 1702 is prepared as 1 M LiTFSI inDME:DOL:TEGDME (volume:volume:volume=58:29:13) with 2 wt. % LiNO₃. Theconventional solvent package is prepared as 1 M LiTFSI in DME:DOL:TEGDME(volume:volume:volume=1:1:1), and the solvent package 1704 is preparedas 1 M LiTFSI in DME:DOL:TEGDME (volume:volume:volume=58:29:13).

FIG. 18 shows a graph 1800 depicting specific discharge capacity percycle number for various TBT-containing electrolyte mixtures, accordingto some implementations. As shown in the graph 1800, “181” indicates anelectrolyte without any TBT additions, resulting in a 0 M TBTconcentration level, “181-25TBT” indicates an electrolyte prepared at a25 M TBT concentration level and so on and so forth. In someimplementations, a 5M TBT concentration level may result in anapproximate 70 mAh/g discharge capacity increase relative to theelectrolyte without any TBT additions.

FIG. 19 shows a first graph 1900 depicting electrode discharge capacityper cycle number and a second graph 1910 depicting electrode capacityretention per cycle number, according to some implementations.Specifically, the first graph 1900 depicts the electrode dischargecapacity per cycle number of an example battery that includes aprotective lattice disclosed herein relative to the electrode dischargecapacity of an example battery that does not include the protectivelattice disclosed herein. The second graph 1910 depicts the electrodecapacity retention per cycle number of an example battery that includesthe protective lattice disclosed herein relative to the electrodecapacity retention of an example battery that does not include theprotective lattice disclosed herein. In some aspects, the protectivelattice may be one example of the protective lattice 402 of FIG. 4.Performance results for both the first graph 1900 and the second graph1910 include usage of an electrolyte prepared with 1 M LiTFSI inDME:DOL:TEGDME (volume:volume:volume=58:29:13) with 2 wt. % LiNO₃.

FIG. 20 shows a first graph 2000 depicting electrode discharge capacityper cycle number and a second graph 2010 depicting electrode capacityretention per cycle number, according to other implementations.Specifically, the first graph 2000 depicts the electrode dischargecapacity per cycle number of an example battery that includes thepolymeric network of FIG. 7. The second graph 2010 depicts the dischargecapacity retention per cycle number of an example battery that includesthe polymeric network of FIG. 7. The battery may be one example of thebattery 100 of FIG. 1 or the battery 200 of FIG. 2. Performance resultsfor both the first graph 2000 and the second graph 2010 include usage ofan electrolyte prepared with 1 M LiTFSI in DME:DOL:TEGDME(volume:volume:volume=58:29:13) with 2 wt. % LiNO₃.

FIG. 21 shows a first graph 2100 depicting electrode discharge capacityper cycle number and a second graph 2110 depicting electrode capacityretention per cycle number, according to some other implementations.Specifically, the first graph 2100 depicts the electrode dischargecapacity per cycle number of an example battery that includes theprotective layer 516 of FIG. 5. The second graph 2110 depicts thedischarge capacity retention per cycle number of an example battery thatincludes the protective layer 516 of FIG. 5. The battery may be oneexample of the battery 100 of FIG. 1 or the battery 200 of FIG. 2.Performance results for both the first graph 1900 and the second graph1910 include usage of an electrolyte prepared with 1 M LiTFSI inDME:DOL:TEGDME (volume:volume:volume=58:29:13) with 2 wt. % LiNO₃.

As used herein, a phrase referring to “at least one of” or “one or moreof” a list of items refers to any combination of those items, includingsingle members. For example, “at least one of: a, b, or c” is intendedto cover the possibilities of: a only, b only, c only, a combination ofa and b, a combination of a and c, a combination of b and c, and acombination of a and b and c.

The various illustrative components, logic, logical blocks, modules,circuits, operations, and algorithm processes described in connectionwith the implementations disclosed herein may be implemented aselectronic hardware, firmware, software, or combinations of hardware,firmware, or software, including the structures disclosed in thisspecification and the structural equivalents thereof. Theinterchangeability of hardware, firmware and software has been describedgenerally, in terms of functionality, and illustrated in the variousillustrative components, blocks, modules, circuits and processesdescribed above. Whether such functionality is implemented in hardware,firmware or software depends upon the application and design constraintsimposed on the overall system.

Various modifications to the implementations described in thisdisclosure may be readily apparent to persons having ordinary skill inthe art, and the generic principles defined herein may be applied toother implementations without departing from the spirit or scope of thisdisclosure. Thus, the claims are not intended to be limited to theimplementations shown herein but are to be accorded the widest scopeconsistent with this disclosure, the principles and the novel featuresdisclosed herein.

Additionally, various features that are described in this specificationin the context of separate implementations also can be implemented incombination in a single implementation. Conversely, various featuresthat are described in the context of a single implementation also can beimplemented in multiple implementations separately or in any suitablesubcombination. As such, although features may be described above incombination with one another, and even initially claimed as such, one ormore features from a claimed combination can in some cases be excisedfrom the combination, and the claimed combination may be directed to asubcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particularorder, this should not be understood as requiring that such operationsbe performed in the particular order shown or in sequential order, orthat all illustrated operations be performed, to achieve desirableresults. Further, the drawings may schematically depict one more exampleprocesses in the form of a flowchart or flow diagram. However, otheroperations that are not depicted can be incorporated in the exampleprocesses that are schematically illustrated. For example, one or moreadditional operations can be performed before, after, simultaneously, orbetween any of the illustrated operations. In some circumstances,multitasking and parallel processing may be advantageous. Moreover, theseparation of various system components in the implementations describedabove should not be understood as requiring such separation in allimplementations, and it should be understood that the described programcomponents and systems can generally be integrated together in a singleproduct or packaged into multiple products.

What is claimed is:
 1. A composition of matter including a plurality ofpores, the composition of matter comprising: a plurality of particles,each of the particles comprising: a first zone including a plurality offirst pores, the plurality of first pores having a uniform pore size;and a second zone including a plurality of second pores, the second zoneconcentrically positioned relative to the first zone and separated fromthe first zone by at least some of the plurality of first pores, whereinthe plurality of second pores has a pore size that gradually decreasesalong a radial direction from the center of the particle to a boundaryof the particle; a plurality of aggregates, each including a multitudeof the particles joined together; and a plurality of agglomerates, eachincluding a multitude of the aggregates joined together.
 2. Thecomposition of matter of claim 1, wherein each of the particles has aprincipal dimension in an approximate range between 20 nanometers (nm)and 150 nm.
 3. The composition of matter of claim 1, wherein each of theaggregates has a principal dimension in an approximate range between 10nanometers (nm) and 10 micrometers (μm).
 4. The composition of matter ofclaim 1, wherein each of the agglomerates has a principal dimension inan approximate range between 0.1 micrometers (μm) and 1,000 μm.
 5. Thecomposition of matter of claim 1, wherein each of the pores has aprincipal dimension in an approximate range between 0 nanometers (nm)and 100 nm.
 6. The composition of matter of claim 1, wherein the firstzone has a first porosity and the second zone has a second porositydifferent than the first porosity.
 7. The composition of matter of claim1, wherein the first zone has a first density and the second zone has asecond density different than the first density.
 8. The composition ofmatter of claim 1, wherein the first zone has a first pore densitybetween 0.0 cubic centimeters (cc)/g and 2.0 cc/g.
 9. The composition ofmatter of claim 1, wherein the second zone has a second pore densitybetween 1.5 cubic centimeters (cc)/g and 5.0 cc/g.
 10. The compositionof matter of claim 1, wherein the Composition of matter has anelectrical conductivity in an approximate range between 100 Siemens(S)/m to 20,000 S/m at a pressure of 12,000 pounds per square in (psi).11. The composition of matter of claim 1, wherein at least some of theagglomerates are connected to each other with one or more polymer-basedbinders.
 12. The composition of matter of claim 1, further comprisingone or more electrically conductive additives dispersed within at leastsome of the plurality of pores.
 13. The composition of matter of claim1, wherein each of the particles includes one or more of flat graphene,wrinkled graphene, a plurality of carbon nano-tubes (CNTs), or aplurality of carbon nano-onions (CNOs).
 14. The composition of matter ofclaim 1, wherein each of the particles further comprises a third zoneconcentrically disposed on the second zone to the center of therespective particle and is separated from the second zone by at leastsome of the plurality of pores, the third zone including a plurality ofthird pores.
 15. The composition of matter of claim 1, wherein theplurality of first pores are macropores, the plurality of second poresare mesopores, and the plurality of third pores are micropores.
 16. Thecomposition of matter of claim 1, wherein each of the particles furthercomprises one or more additional zones concentrically disposed on thesecond zone to the center of the respective particle and each of the oneor more additional zones is separated from an immediately adjacent zoneby at least some of the plurality of pores.
 17. The composition ofmatter of claim 1, wherein the pore sizes of pores of the plurality ofsecond pores gradually decreases along the radial direction.